My 2009 RX8 had its battery replaced at 1,600 miles and NOW at 6,000 miles the battery again is dead and needs replacing. Mazda has been running tests on it for 3 days and so far no luck pinpointing what is draining the battery. Has anyone come across a problem like this, and at what point does this become a lemon on my hands? =( So basically I'm on my third battery in 1 year!

WOW that's not normal at all. To me it sounds like more than a draining issue. I'm wondering if the alternator isn't overcharging, if not all the time just some times, enough to damage the battery.

Assuming you're in California, here's some info on the lemon law there: link