Yeah, the fact that it searches for terms you don't type in has really been annoying me for a while. You essentially have to put a + in front of every term in a technical search. I have to say, though, it makes sense for non-technical users, who are apt to type in misspelled and suboptimal terms. For the vast majority of users, Google probably knows better than they do what they should be searching for. Also, I think this change may have evolved as a more generic implementation of an attempt at stemming. For example, it makes sense for Google to additionally search for stereos when you enter stereo, and brings, bringing, and brought (and probably brang and brung) when you search for bring.

Another bugaboo of mine, though, is the fact that hyphenating words no longer acts the same as putting them in quotes. Searching for car-stereo used to be the equivalent of "car stereo" — one less character to type. Now Google ignores the hyphens.