Ha! This is pretty cool! Somewhat old sounding, almost 50's but with a modern touch. You're definately doing something right.
The one thing that I really think would help your overall sound would be a real bass guitar. Weren't you the one who was pitching the guitar to sound like a bass? Anyway, a fuller bottom end would be great.
You might also try a few more takes on each instrument to get the whole thing tighter sounding. I know that's never fun and can take some of the fun out of the sound. (I'm very guilty of calling it "good" also...one or two takes max) The bass, for instance, gets off here and there and kind of cuts out in places. This is a personal taste issue though.
Catchy and simple, I like! Kind of reminds me of the Foo Fighters.
Slackmaster 2000
Ciao!