Fresh. Friendly. Free
Didn't really like the emphasis on "free" though. I know free has a different meaning when it comes to software, but people new to FOSS will perceive LM as nothing more than a "free" but possibly inferior (due to cheap cost) alternative to Windows, when it is far from that.
Linux is now easy.
Heh.. this one is good. Maybe as an alternate or a secondary slogan, or something of that sort.