bitcoin will be around for a long time i guess see the latest price rising and current volume of bitcoin traded on market now more than few thousand with only 1 exchanger ,i see the disadvantage is the fluctuation because when the customer paying with bitcoin it take a time to get confirmed so at this time it'll posibly the value of bitcoin become lower or higher,but if you simply use a bitcoin payment gateway API by bitpay or coinbase you don't need to worry about this,however so many online company right now accepting bitcoin even big companies,especially those cloud "things" providers such as cloud server or anything else
about security issues,if you'd use bitcoin payment gateway API , i think there's no any security reason which could possibly threatening,all the problem will be resolved by the API provider i guess

Don't worry about Bitcoin as a declining in the future, I can see it will be bigger in a long term

The only disadvantages about bitcoin that I could think is confirmation time, If your customer is paying through bitcoin with low fee for miners then the coin can arrive in your wallet for a long time, can take up to 24 hours and at that time the price could go rise up higher or go down

as Aubert says, use payment API like coinbase

If you still wondering how tough bitcoin is go take a look at this articles
https://99bitcoins.com/bitcoinobituaries/
That website listing all of news about speculation that bitcoin will died, which already happened 106
For a currency that's pretty strong

Bitcoin has potential, and I think as long as there are no problems in its development, it will continue to attract peoples.
The price of Bitcoin change a lot, which can be favorable or unfavorable.

I think this is great for the betterment of your website. Because bitcoin is already as famous for ease of payment, security matter that depends on your website data base. because I do not think anyone could broke into bitcoin wallet without knowing the password or private key. Thank you

I don't see any reason for bitcoin to decline, infact more and more companies are offering bitcoin as their new way of payment. And if you did the same, you surely contribute on bitcoin's popularity and that will help as alot who wants bitcoin to circulate.

Depending on your licencing model/technology, the long confirmation times might not be a problem.
If your client needs an active licence that is checked often (each startup, every 24 hours, at random intervals,...) you can deliver a licence as soon as somebody broadcasted a transaction (allowing 0 confirmations). If the transaction isn't confirmed after 24 hours, or if the inputs get double spent, you can just withdraw your licence, so the person trying to scam you just had a free demo, but was kicked out before he had practical use for your software.

If it's a web-based service, it's even simpler... Just lock their account if the transaction isn't confirmed after 24 hours, no worries  

It would be a whole different thing if you were selling physical goods... Once they are sent, it's pretty hard to get them back if the transaction doesn't confirm, or if the sender double-spends. Same thing goes for a lot of digital downloads that don't require a licence, but in your case, i don't see a problem.

Accepting bitcoins as payment from your customer is nice since it could possibly increase the number of your online clients. But before you engage in bitcoins as mode of payment please consider the processing time before you receive your clients bitcoin it will took an hour but on rare occasions in days. So if your transaction time at present is faster you should study first how bitcoin process is done.

If it's going to cost you large amounts to integrate it into your site I'm not totally sure it's going to be worth it. Most Bitcoin users are hoarding it. A few true believers might spend with you. Either way you're not going to be snowed under with new users because of it.

Who said ? Being a developer myself,doesn't cost you anything but two hours of API integration as long as only the payment system implementation needs to be done.True that he won't be showered with users on the day 1 but certainly not a bad idea to do so.It would be a good alternative to the users apart from the regular payment methods.You will always  be a step ahead in terms of technology.Go ahead with the idea,you have nothing to lose.

The security is flawed with your regular digital payment systems.Bitcoin is comparatively less prone to that.What could one possibly do with bitcoin payment system anyway ? Steal your coins ? I don't think so.People would embrace the change and they'd have one more place to spend their bitcoins.Don't use bitcoins because of its popularity but the efficiency.Speaking of which,I don't see it getting less popular anytime soon.The implementation costs are less,you can set up a payment system in couple of hours.