All of this story tell us something.
We now know that someone out there is able to crack aprox. 2^50 private keys in about 1 year. 
(in a worst case scenario, also assuming that the one who cracked the 50 addresses brute forced all the possible addresses sequential)
As time goes by this capability will increase, it may take decades and decades or centuries but eventually it will be possible to crack 2^256 pvks.
The transaction referenced in this thread is a good reference to test how far the mankind cracking capabilities are.
As of now, we can enjoy the safety of bitcoin for a long long time 

2^1   2   
2^2   4   
2^3   8   
2^4   16   
2^5   32   
2^6   64   
2^7   128   
2^8   256   
2^9   512   
2^10   1024   
2^11   2048   
2^12   4096   
2^13   8192   
2^14   16384   
2^15   32768   
2^16   65536   
2^17   131072   
2^18   262144   
2^19   524288   
2^20   1048576   
2^21   2097152   
2^22   4194304   
2^23   8388608   
2^24   16777216   
2^25   33554432   
2^26   67108864   
2^27   134217728   
2^28   268435456   
2^29   536870912   
2^30   1073741824   
2^31   2147483648   
2^32   4294967296   
2^33   8589934592   
2^34   17179869184   
2^35   34359738368   
2^36   68719476736   
2^37   137438953472   
2^38   274877906944   
2^39   549755813888   
2^40   1099511627776   
2^41   2199023255552   
2^42   4398046511104   
2^43   8796093022208   
2^44   17592186044416   
2^45   35184372088832   
2^46   70368744177664   
2^47   140737488355328   
2^48   281474976710656   
2^49   562949953421312   
2^50   1125899906842620   <- This is aprox. the number of bitcoins private keys someone is able to crack in about 1 year
2^51   2251799813685250   
2^52   4503599627370500   
2^53   9007199254740990   
2^54   18014398509482000   
2^55   36028797018964000   
2^56   72057594037927900   
2^57   144115188075856000   
2^58   288230376151712000   
2^59   576460752303423000   
2^60   1152921504606850000   
2^61   2305843009213690000   
2^62   4611686018427390000   
2^63   9223372036854780000   
2^64   18446744073709600000   
2^65   36893488147419100000   
2^66   73786976294838200000   
2^67   147573952589676000000   
2^68   295147905179353000000   
2^69   590295810358706000000   
2^70   1180591620717410000000   
2^71   2361183241434820000000   
2^72   4722366482869650000000   
2^73   9444732965739290000000   
2^74   18889465931478600000000   
2^75   37778931862957200000000   
2^76   75557863725914300000000   
2^77   151115727451829000000000   
2^78   302231454903657000000000   
2^79   604462909807315000000000   
2^80   1208925819614630000000000   
2^81   2417851639229260000000000   
2^82   4835703278458520000000000   
2^83   9671406556917030000000000   
2^84   19342813113834100000000000   
2^85   38685626227668100000000000   
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2^202   6427752177035960000000000000000000000000000000000000000000000   
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2^209   822752278660603000000000000000000000000000000000000000000000000   
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2^211   3291009114642410000000000000000000000000000000000000000000000000   
2^212   6582018229284820000000000000000000000000000000000000000000000000   
2^213   13164036458569600000000000000000000000000000000000000000000000000   
2^214   26328072917139300000000000000000000000000000000000000000000000000   
2^215   52656145834278600000000000000000000000000000000000000000000000000   
2^216   105312291668557000000000000000000000000000000000000000000000000000   
2^217   210624583337114000000000000000000000000000000000000000000000000000   
2^218   421249166674229000000000000000000000000000000000000000000000000000   
2^219   842498333348457000000000000000000000000000000000000000000000000000   
2^220   1684996666696910000000000000000000000000000000000000000000000000000   
2^221   3369993333393830000000000000000000000000000000000000000000000000000   
2^222   6739986666787660000000000000000000000000000000000000000000000000000   
2^223   13479973333575300000000000000000000000000000000000000000000000000000   
2^224   26959946667150600000000000000000000000000000000000000000000000000000   
2^225   53919893334301300000000000000000000000000000000000000000000000000000   
2^226   107839786668603000000000000000000000000000000000000000000000000000000   
2^227   215679573337205000000000000000000000000000000000000000000000000000000   
2^228   431359146674410000000000000000000000000000000000000000000000000000000   
2^229   862718293348820000000000000000000000000000000000000000000000000000000   
2^230   1725436586697640000000000000000000000000000000000000000000000000000000   
2^231   3450873173395280000000000000000000000000000000000000000000000000000000   
2^232   6901746346790560000000000000000000000000000000000000000000000000000000   
2^233   13803492693581100000000000000000000000000000000000000000000000000000000   
2^234   27606985387162300000000000000000000000000000000000000000000000000000000   
2^235   55213970774324500000000000000000000000000000000000000000000000000000000   
2^236   110427941548649000000000000000000000000000000000000000000000000000000000   
2^237   220855883097298000000000000000000000000000000000000000000000000000000000   
2^238   441711766194596000000000000000000000000000000000000000000000000000000000   
2^239   883423532389192000000000000000000000000000000000000000000000000000000000   
2^240   1766847064778380000000000000000000000000000000000000000000000000000000000   
2^241   3533694129556770000000000000000000000000000000000000000000000000000000000   
2^242   7067388259113540000000000000000000000000000000000000000000000000000000000   
2^243   14134776518227100000000000000000000000000000000000000000000000000000000000   
2^244   28269553036454100000000000000000000000000000000000000000000000000000000000   
2^245   56539106072908300000000000000000000000000000000000000000000000000000000000   
2^246   113078212145817000000000000000000000000000000000000000000000000000000000000   
2^247   226156424291633000000000000000000000000000000000000000000000000000000000000   
2^248   452312848583266000000000000000000000000000000000000000000000000000000000000   
2^249   904625697166533000000000000000000000000000000000000000000000000000000000000   
2^250   1809251394333070000000000000000000000000000000000000000000000000000000000000   
2^251   3618502788666130000000000000000000000000000000000000000000000000000000000000   
2^252   7237005577332260000000000000000000000000000000000000000000000000000000000000   
2^253   14474011154664500000000000000000000000000000000000000000000000000000000000000   
2^254   28948022309329000000000000000000000000000000000000000000000000000000000000000   
2^255   57896044618658100000000000000000000000000000000000000000000000000000000000000   
2^256   115792089237316000000000000000000000000000000000000000000000000000000000000000   <- And this is how safe bitcoin is.