Have purchased different versions of Gevey SIM umlock cards through eBay from a supplier in HKG - from 2.0.2 to 2.2 (used the 2. version fom beginning of Dec 2008) and found the cards to be reliable and does work. They have just released Gevey 3g PLUS 2 which is supposed to work on baseband 2.3. All the cards cost me only about USD8.99 each with free shipping and I have used the earlier Gevey cards even before the Dev team release their unlock functions and all the unlock cards worked.
Based on this experience, I would trust that their 2009 version will work for baseband 2.3.
Do not know when the Dev team will release thier unlock apps.
No harm spending less than RM30 to try instead of having a expensive iPod for a few months.
Received my cards about 7 working days from the time when I ordered the cards. I am not promoting any of these suppliers but you could check them out on eBay.

The only problem is that you will need a new SIM unlock card every time you upgrade the baseband by mistake!