Yeah, I thought it was a really bad year. I'd speculate that it has to do with the fact that over the last two years the longstanding Atlanta drought has abated, but I don't really know.
As far as boric acid, I've had REALLY good results with that on carpet. I get some stuff called Flea Busters that I've been told is "safe enough to eat." It's sort of pricey and you have to get it off the internet. I think the main difference is that it's granulated instead of powdered, but I have no idea why that would make a difference. It does though. In 1995 I was living in an apartment with my first dog and the fleas were absolutely godawful, much worse than this year. I tried everything. Nothing helped for more than a day or so until a vet suggested this stuff. Highly recommended.