Both are great games, I think CoD doesn't have as good an online community as Vegas 2 does, but it probably has more online players. Both of them are quite realistic compared to something like Halo, and both require skill.
I'd say if you want a more tactical, realistic shooter, go for Vegas. If you want a quick, fun shooter, go for Call of Duty.

Both games make it easy to play with friends and other players.

http://lifehacker.com/software/step-by-step/share-your-macs-printer-with-windows-without-samba-310554.php

Maybe that's worth looking at

Planet Earth BBC Edition on Blu-RaySpruceCaboose

I love you.

Earth Defence Force 2017 X360
Beautiful Katamari X360
Ratchet & Clank PS3
Mass Effect X360
Bully X360
LEGO Star Wars X360
Unreal Tournament 3 PS3
Assassin's Creed X360
Army of Two PS3
Haze PS3
Time Crisis 4 PS3
Call of Duty 4 X360

Hope to get most of these by the end of the year.