Do the wallet.dat and blockchain files from qt 0.8.5 work with it? I'm gone for a month
and the qt option disappears! lol I hope it's mostly just a renaming of the program.
your wallet.dat is holding private keys - this is most important file as you know - there are your Bitcoins
your wallet.dat will work with Bitcoin Core 0.9.0.
You can put old blockchain too - core 0.9.0 will update it anc synchronize.
If you will have any problems - aks
Just remember to keep wallet.dat safe.