I've played Halo on PC when i was younger, and since i don't have a console i kinda had to stop at the second one (they stopped pc support after the second game). Currently due to real life stuff (mainly education) i don't think its good to buy a console and start on another game series

Would the xbox360 (as well as its games) be around for a few more years? How long do you think it'll be around for? I'd be a sad kid if it gets liquidated in the near future

I would guess that quality games will still be made for the 360 for another 4-5 years. The Xbox One version will just be more popular.
And even after that, the occasional game will still be made. The 360 probably still has another 10 active years of life in it.

To put it in perspective, the last Playstation 2 game was released the same month as the PS4 launched.

Considering I still have my NES, SNES, Sega, PS1, PS2 and Xbox, I would say that the console and the games will be around as long as you keep them around. As for developers, they will develop for the platform that meets their needs and gives them a market to sell to.

The good thing about old consoles is, the games get real cheap when the distributers start clearing out their warehouses. Look for the bins in the stores when this happens and dig through there for the games you wanted to play, but did not want to pay full price for.