I'm closing in on 500 BD... 
I've got 3 BD compared to my 2,000+ dvd's
Still too expensive for me to go out and start rebuying everything all over again. I'm sure there would be another new format out in time before that ever happens.
You've just got to keep an ear to the ground...
Just today WBShop.com had 30 or so movies on sale for $4.95 each, if you bought 4 or less. Shipping was $5.00
I put in two orders... 8 movies, a little over $50.00. Plenty of good titles there too, some of the ones I ordered were Natural Born Killers, Mystic River, Wild Bunch, Robin Hood Prince of Thieves, Deliverance, Observe and Report... That sale only lasted a few hours though.
If you haven't been yet, blu-ray.com has a very active forum dedicated to sales... I check it each morning at work and sometimes there are incredible deals out there. But yeah, if you walk into Best Buy and shell out $26.99 + tax for every new release, it's absurd.