PS3 or PS4. What to buy now?

Hi all,

I am thinking of buying a PS. I cannot decide if it is the PS3 or PS4. I want to buy a PS4 because it is the latest technology and if past is any indicator, it is guaranteed to get games for at least another 7 or 8 years. I already have an XBox 360 and love it. I used to play my brother's PS3 and loved it too. Too bad I moved to a different city. Now I have to buy one. The reason I am confused is because I am a great fan of Infamous and Uncharted series and the PS4 doesn't play PS3 discs. The digital download does not guarantee if these games will be available. I want to get the PS4 but I don't want to miss out on awesome PS3 franchises which I have not played completely yet. I Still have Uncharted 2 and 3 and Infamous 2 to play and many other PS3 exclusives.

What do you think I should do?

Thanks.