Um...how reliable is the PW stats tracking? I just started advertising a little under two weeks ago, and according to their chart yesterday's traffic was nearly 5,000 uniques above when I started (a 1,000% increase). It's weird because I added up the clicks from all my ads and it totalled to under 500

Someone posted a link to a traffic analyser a while ago, but I can't find it now. I need to double check this. Something's either Very Wrong or Very, Very Right.
When I'm not advertising, PW displays my stats at reliably about 150% of my Analytics stats.
When I am advertising, though, it displays my unique visitors at over 600% of what my actual traffic was according to my other metrics. It's my hypothesis that PW vastly inflates your unique hits from referring sites in order to give you positive feedback from making bids. The reason I think it's inaccurate when I'm not advertising, then, is because I get hits from bookmarks on Belfry and WebcomicList and so forth.
Um, also, don't forget that even the most accurate metrics are still voodoo. I like analytics the most because it displays time on site and pages visited so you have a firmer idea of who's a robot and who isn't. Don't forget you're not seeing people with adblock and noscript, either.