Citrix have finally announced that FP2 will be released on 29/09/09.
Healine features:
It will be available as HRP05 for XenApp 4.5 and 5.0 installations.
There's some interesting limitations in the HDX Mediatream for Flash support in that your client will need direct access to the source of the flash content (e.g. internet access) as the flash content is no longer sent via an ICA virtual channel (as it was in the tech preview). Citrix removed this feature due to "security concerns" so it's likely to re-appear in a future version or service pack.
It does limit the functinality somewhat, in that your clients will need internet access (direct or via a proxy) to be able to fetch the flash content themselves. This has knock on effects to WAN acceleration, bandwidth etc that will need to come out in testing.