On 11th May, 2012, 18,547 BTC were reported stolen from bitcoinica.com as stated here: https://bitcointalk.org/index.php?topic=81045.0
The bitcoinica.com website is unresponsive at the time of writing this. Are they planning to reopen? Have they stated whether their users’ deposits will be refunded? If yes to either of those question, have they give a timeframe?
Zhou tong has stated here that reopening is being considered, with a time frame of several months.
He has also stated that deposits will be refunded; Most recently, he has stated that a claim page has been opened at https://claims.bitcoinica.com/, but at the time of this writing it seems to be unavailable.
Update: I can now access it.