I just had the same problem, and it is not resolved yet. It took about an hour for the transaction to be "completed" on the TradeHill site, and it's now been about 20 minutes with no activity in my Bitcoin client.
This is not cool at all, even if it gets resolved in the next minute.
I was going to move some Bitcoins back to Mt. Gox because I can't even get a full account history on Tradehill, and I always have to do the math myself to figure out what price my trades settled for. It's interface is slightly nicer than Mt. Gox's HTML for Dummies, but my trust for Tradehill has gone downhill. Their main marketing point seems to be their affiliate program. I've got free trades on Mt. Gox for the next month, so I'm back to them, and I'll hope for a better exchange from someone in a month.