I don't really mind the top tab bar, but I think it's hilarious that Woot! needs to explain the sites. Wait, sorry; I misspelled "sad." Anyway, I'm not using the bar, because the photos with the rollovers on the right side are so much easier.
Also, here's the practical reason I'm likely to buy less: Before, I load the page, quickly see whether I'm kind of curious about the product, and scroll down to the list of features to try to talk myself into buying it. I can't do that now; it's become a quick glance to see if the daily product is anything I need, and if it isn't, I'm not going to bother to click to see the features.
As for ads.. what ads? I run three ad blockers. Anyone who isn't using at least one gets what they deserve...