WD MyBook Studio Suddenly Slow. Sign of Failure?

Hey Guys.

I have a Western Digital MyBook Studio 3TB external hard drive that has suddenly slowed down dramatically.

I usually hook it up with FireWire 800, but both FireWire and USB is slow. I've hooked it up to another Macbook and it's still slow so i know it's a drive problem.

The speed is so slow it takes about 30 seconds for drive to load thumbnails, and videos do not even load.

I have read through many many forums but still unable to find a fix. I have a lot of important Data on this drive that i cannot lose. It's basically everything digital i have/own.

Details that may help

-2010 27" iMac i7.

-I have owned this external drive for about 6 months, and it has been working perfectly.

-There was a power outage a couple of days ago, it worked fine immediately after but the problems started yesterday.

-Currently, the drive is about 1tb used and 2tb free.

-I've tried PRAM reset, different cables, removing the drive from index, pretty much everything i found on forums but no luck.

-drive not making any odd noises or clicks.

Please help as i cannot afford to lose the data on this drive.