Ayra, very good call on Shepard. As you can see, I agree with you there and made femShep my #1 choice.
J, as far as I can tell, Beyond Good and Evil HD is only going to be available on the PS3 and 360. But if it sells well, it isn't hard to translate from the 360 to Windows so, hopefully it'll show up on Steam.
Soysauce, I considered GlaDos but, unfortunately, I played Portal in 2009, not 2010. Otherwise she might have made the list.