Friend's 18th Birthday: New game system?

18th is sort of a milestone, and I'm wondering if a new video game system (haven't decided on 360, PS3 or Wii) is appropriate for this occassion. Keep in mind he considers this his "adult" transformation, and of course he's right, politically anyway.

Thoughts? 

Also, I realize this isn't System Wars, but any suggestions as to which system is best ATM? (I'm purely a PC gamer, I have no freaking clue). 

For my Friends 18th birthday he got an X-Box 360 because he really likes Halo.  So take that as you will.  I only have a PS3 and I'm enjoying it but I have a whole bunch of PS2 games to play while I sit and wait for the good stuff.  If he likes movies and thinking of moving past DVD's maybe a PS3 for the Blu-Ray but other than that I say an x-box 360.