I just deposited 1.5 BTC into my QT client wallet a minute ago, but now the new BTC AND the transaction all disappeared from my QT client main screen. Also I'm seeing all these warning about a blockchain fork, should I wait or change my client to 0.7?
If you're mining, make absolutely sure you're using Bitcoin 0.7 or lower. Do NOT use Bitcoin 0.8.
If you're not mining, do nothing and wait for the all-clear. Running Bitcoin 0.8 as a node is fine so long as you're not mining.