Guild Wars 2

Seems interesting:
http://research.microsoft.com/en-us/projects/trueskill/faq.aspx

But probably would cost a lot for ArenaNet to “buy” it from or be able to use it since it is from Microsoft – or they would need to make something similar which probably is not easy and needs a lot of work.

Also people talking here: http://www.gamereplays.org/community/MS_True_skill_is_crap_on_a_stick-t447220.html
say it’s crap.

Has anyone played some team-based games using that system?

you have yet to see my trueskill