Playing Devil's Advocate Here (pure evil speculation on my part) my real views are opposite..but just to walk on the 'dark side' for a moment...

just to take the other side (which most economist's take yet on bitcoin) you could have the 'worst of both worlds' ie difficulty goes up and up at a pre-arranged set pace of difficulty due to $$ and infrastructure already in the pipeline but due to "silly primate humans" that we are and the fragile psychology on our thoughts...the demand to use bitcoin does not keep up....ie the small miners the cheerleaders of bitcoin drop out and hold more then they invest either in miners or btc...the general public is told bitcoin is a scam by those who have the power to move money now..and want it to fail....and it flatlines.....to a point where it is impossible to stay up and keep the ballon filled (ie the difficulty problem of equip investment) because demand/pressures by gov'ts and just not enough individuals to move bitcoin along the timeline....then the next crash....happens for whatever reason say Venezuela bans bitcoin or some other heavy handed move by a gov't ...  it will be 'big money investors' not people who believe in bitcoin yelling for their investment back sell sell and boom...tulip craze bust.....again taking the opposite argument for devils advocate sake....

truth be told if I was the head of google or apple or some such 'player" of note.... right now or say steve jobs was still alive ...I'd get a bunch of corporation types together and say we are gonna get on the virtual currency bandwagon....we are gonna make something called say xxxxcoin  or some such and it will be backed by some major corporations say 40 or so...BUT instead of doing like corporations do and try to control the whole situation. They announce it is sha-256 independently run just like bitcoin they are hands-off completely ...just their reputations for taking this coin to the future is on the line....and they announce such a coin sha-256 difficulty 0 will start with no pre-mine at midnight june 1st 2014 say

all hell would break loose IMHO ....my then defunct bitcoin knc 555gh miner at that point would be fired back up along with every laptop computer..USB ASIC 333mh unit I had...it would be a wild ride with all the obsolete sha-256 ASIC hardware out there getting a NEW life...talk about speculation!....all the stuff out there and/or GPU bitcoin rigs drag'd down from the attic..would be quite the hoot IMHO

even if it was only as successful as litecoin and or this was done mostly as PR for the various corporations involved....they likely would have more influence if not then later
on how alternate currencies are used/made/controlled in the future (just look at the push for getting rid of net neutrality on the internet by corporations who were on the bandwagon in the past)

but it never will happen ..(steve jobs might have done it for kicks/fun and PR but don't see anyone else with the b*lls)...they will always have to have a hook into the coin
to do so some kinda catch (even in the above case the catch would be to kill bitcoin)....and corporation  types are so short term motivated by 2yrs max....it will never fly

but again if I ran google/apple or whatever... I'd do this for the PR and just to shake things up towards regulation .which is what these large banks and corporations want with virtual currencies to trend to anyway...the option to influence at best and control at worst in the future...but it is unlikely they would have the skills to play this "long game" on virtual coins IMHO

(these dark times brought to you by my demented mined....don't get me going on zombies it could get worse)

anyway this nightmare will not happen..but if I had a billion dollars I could have a lot of fun with PR just throwing this idea around

(the lengths I'll go to keep my old ASIC gear running)

Searing