Just realized my camera is really outdated, need some opinions

I've had this camera for 5 years now and I really like it, but it's getting slow. I also just realized it's only a 10mp camera. It's a Canon PowerShot SD790 IS Digital Elph.
My camera on Amazon $500 new, and $100+ used :rolleye2:
http://www.amazon.com/Canon-PowerSho.../dp/B0011ZK6OS

My dilemma is that I want a newer camera with better mega pixels and higher zoom. I know I get can get higher mp and op zoom for $100-$200, but when I look online people are still wanting a ton of money for the camera I have now. Am I going to be super disappointed with a $100-$200 camera after using this one or will it be worth it? I really like this camera because I can turn the flash brightness up or down. The problem is I don't want to spend an arm and a leg on a camera when I have one that works.

This camera takes decent pictures, but it's getting slow and the image stabilizer isn't working half as well as it used to.
http://i157.photobucket.com/albums/t...Isis/025-6.jpg