TechieGuy that's great! Every now and then I'll get a surge from stumbleupon too and even though it's short-lived, it's still nice to get the extra visits. Just think... even if only a handful subscribe to your RSS feed that's still well worth it. Congrats!
I didn't realize you wrote reviews for other blogs. Great tactic. I've heard a lot of people finding success doing that. Good for you.
Seems like a great way to build traffic long-term.