Good idea to start the discussion!
The site you are looking for is
http://www.ncsl.org/More specifically
http://www.ncsl.org/ncsldb/elect98/partcomp.cfm?yearsel=2004for control of legislatures. Yes Ne and Me are the only states so far to have a different system. As to who is considering it? We'll I'm guessing all the states controlled by one party, but which usually votes for the opposite party for President have it in mnd but no one is actively considering legislation.
I do remember legislation to this effect being intoduced in North Carolina (by a democrat of course) It must have died a natural death when the GOP took the lower chamber in 2002.