I upgraded to 0.8.4 on OS X 10.8 without issue, no DB corruption or whatnot, HOWEVER, now I made my first transaction since upgrading and I can't get the transaction to confirm, it has been 1.5 hours since the transaction and NOTHING... ZERO confirmations. It says the following: Status: 0/unconfirmed, broadcast
Your transaction should be fine if you just leave your node running it will rebroadcast it periodically.
To be more sure about it, open up the debug console (help -> debug -> console) and type
getrawtransaction 1
e.g.
getrawtransaction eb61f51fe142ff46958cf1f98d31a1a5cdbcab4a766b711fc9f2fb8e2cb4504f 1
And paste the result and we can look at the transaction and potentially rebroadcast it.