BlazeDS integration is on the roadmap for a future release of Open BlueDragon (hey, give us a break, we have more cool stuff planned than we can keep track of!), but in the mean time I've put together an OpenBD + BlazeDS HOWTO on the OpenBD wiki.
Note that the HOWTO is really more of a guide for gearheads (like myself) who are interested in how all the pieces fit together. If you just want to grab a clean slate on which to mess with things, or see a couple of very simple sample Flex apps in action, you can do that too:
Next step is to rework the OpenBD BlazeDS adapter to support returning queries directly to Flex, and then Flex lovers are in decent shape on OpenBD until we do the official integration.
Thats cool. Thats real cool.