My withdrawal is stuck too. There's another discussion about the problem here.

See if you can find your transaction id in the list here: https://data.mtgox.com/api/0/bitcoin_tx.php

There are two fields to each transaction, "hash" and "tx". You can copy/paste the "tx" field, which is the raw transaction in base64, convert it to hex, and then use https://blockchain.info/pushtx to re-submit the transaction. From there you can get additional information on the problem.

On the other thread, one of the inputs to his withdrawal was already spent ("An outpoint is already spent", double-spend). In my case, I got "Unable To find all tx inputs" (3 of the 4 tx inputs were good, but one was not).