It was pretty much the same story for me. I played and enjoyed the first Prime, but got distracted by a shiny new game. I had a Gamefly subscription at the time Prime 2 came out- so I rented it, played it a bit, thought it looked great and bought it out (Gamefly let you buy your rentals at a discount). But, I didn't want to get too far into the game before I finished the first one.

I'm trying to get into the "Froggy" method of gameplay now where I try to focus on/complete just a couple games at a time before bothering to pick anything else up. Trouble is, so many new, good games seem to be coming out.... The temptation of going straight to Prime 3 is mainly the controls. All 3 should be fun gameplay-wise, but it sounds like Prime3 is the first Wii game to really nail the FPS controls. Being able to play a Prime game with highly intuitive controls is quite a draw.