According to this article at Hexus, the G45 is having some trouble and will be delayed another 3 weeks past the P45. We might see these in the channel in August. Seems to be a trend with these next-gen IGPs...
There's a site in Canada, RB Computing, that lists availability of the DG45ID (that's the micro-ATX Icedale). I haven't contacted them to find out if it's a mistake. I'm waiting for the DG45FC (mini-ITX Flying Creek) anyways.
Update: The site has been updated to show no availability, however it's the only place I've found that even lists one of the upcoming Intel G45 boards.