Dude.. You will absolutely LOVE the 5D Mark II. You might find the controls abit confusing at first since you're doing such a huge jump. I was lost when i first upgraded from the 450D to the 50D.
Those shots are great! Love the colors and framing. What post work did you do on the 2nd shot? I like the way that turned out. Vouch the glass is a pain in the butt!! They rage me everytime i go to the aquarium. They have those uber thick acrylics that distorts the fish if you look at it from an angle. Popping a flash at them will definitely help improve sharpness though.
Heres a shot i took a week ago at the aquarium. I found this little guy hiding alone in one corner away from all the other fishs. Bullying is bad mmkay.

http://i105.photobucket.com/albums/m223/Jdmhoodz/_MG_8245-2.jpg
Amazing.