Wallet on Windoze seems fine to me.  No transactions yet but I synced the chain and connected to 8 nodes.  If I earn anything on testnet mining I assume I"ll see at least one transaction, but can't confirm that yet.  Regarding the website countdown, I also see that it added 12 hours which makes me wonder if it's even real or just a placeholder.  I assumed they were counting down to a midnight ET launch.  Would be nice to know when to expect it.

EDIT: I found several blocks on the testnet but never saw any coins attributed to my account or transferred to my wallet on the testnet.  Not sure if there should have been but if we're testing real world functionality I would assume it should work just like the mainnet will.