Aka RoE. Possible spoilers Ahead, be warned.
1.0 was released in 2007, and I found out about it over at 4chan (torrents) a few months back.
Managed to watch 2.0 in the theatres over the weekend.
Having watched the original series back in the late 90s, I find myself comparing the scenes and generally trying to spot the differences. I still enjoyed the movie thoroughly.
1.0 has mainly has the same storyline minus the lull moments and covers up til the cube angel that tries to drill its way down to NERV.
2.0 picks up from where 1.0 left off and is mostly different from the original. Alot of kick ass new scenes added in and even a new character. Asuka gets a new surname. Shinji is less wussy (there's a gurren lagaan reference near the end sequence, I think).
You may not understand what is going on in 2.0 if you have never watched the original Eva animation before though.
I just might go back to the theaters to watch 2.0 again this weekend. It just isn't the same as watching at home with my lame PC speakers.