When I upgraded to 0.8.1, it said Reindexing blocks on disk and it took about four days (Grr). But later, it said something about a corrupted database and it had to do it again! What is it doing?
The way the blockchain is stored on your computer has changed with the latest version.
The developers tweaked it, so that future users can profit from a faster init-proccess.
The new indexing made it necessary to reinitialize your blockchain.
However it should not have taken so long. On my laptop it took about 2 hours. Do you have a very weak computer?