Yeah, I would have to agree there. In the past the reverse engineering was focused primarily one a few concentrated areas which were ALWAYS commerce related. With adsense, everything is fair game, and yes, it it is a helluva lot harder to find the right info now.
As for g's overall improvements, I would say they have improved a bit in terms of getting complete junk out of the index, but this is one piece of the puzzle.
As for relevance and quality serps, it has suffered. Seems like along the way, every little change has hurt the BEST sites on the web. The niche authority sites, the interesting and even FUN sites.
I think many here are now programmed into thinking big, mega million dollar companies provide the most useful, interesting, or even important information when, in fact, it is mostly utter crap. And the guy who writes his arse off about a topic he KNOWS and loves gets pushed to the back in favor of cookie cutter content from semi relevant sites. Sure, many of these sites used SEO techniques that google may not like, but the final result is just worse. I would rather see the old google, even if it had a bit more clutter (not sure it did).
whew...that was tough... :)