factory incentive rebate and holdback

Hello,

I'm shopping for my second Prius and will be buying the Prius II (I never used the bells and whistles of my first top-of-the-line 2005 Prius).

I'd like to get a good idea of dealer cost. Does anyone know what the current factory incentive rebate and holdback is right now (April 19, 2010)?

I've got an online source that says the invoice is $20,900 and another at $21,400.

Thanks in advance!