Hmm, I didn't see much point in FreeCiv- I played it it all just seemed the same (I didn't play it for very long, and it was quite a while ago, so I may be wrong)
However I like FreeCol, or, I will once the bugs are ironed out and it gets to the full version... Colonization was a good game just a little dated (how those graphics made my eyes sore...)- since it's largely been abandoned, I'm glad someone is picking it up to improve it, first graphically, then technically
And it's free too- to a cheapskate like me, that's ALWAYS important