Hmm ya, I could certainly see a positive feedback loop developing. Out of curiosity, do you regularly log into a google account and/or use services like gmail? I'm guessing not, since presumably that would give it plenty of data. (Unless you actually are a spammer... ;) ) Also, are you connecting from a location that Google might see as more likely to produce spam? (I would guess any non-"western" country to some extent, with Nigeria likely being at the far end of the scale.)