Well your friends all own a PS4 already so that is a big reason to get one already
However i'll tell you the reasons I chose ps4 this gen.
First of all the track record and the amazing support the PS3 got towards the end of its life was a big factor as well as the great first party studios and exclusives that sony has. This plus the fact that PS Plus offers better free games, the controller is better, the console and OS looks nicer and runs smoother as well as the fact that pretty much every multiplatform game will run better on PS4. I believe that PS4 is the better long term investment. As for me right now I see XB1 as an impulse buy just because they have a few games out now, although I think they've put all their eggs in one basket and the lineup will be pretty dry most of next year. If I did buy an XB1 I honestly think it would be a waste of my money as I already have a PS4 which I believe will be much better overall throughout the whole gen.
EDIT: I'd just like to add that I haven't really had a console that most of my friends own since the PS2 and trading games again is awesome! Saves so much money