Jan Ozer put together a synopsis of Blu-Ray authoring options entitled Levels of Blu-ray Disc Authoring on the EMediaLive website. May be worth a read.
I've aleady seen what DVDa can do and I am NOT impressed. it's a good program with a good work... just WAY too "recompress happy".
At this point I'm seriously considering DVDit Pro HD... although the Author got the price wrong. $299 will give you the NON hd program. For Blu Ray the program is the HD version at $499.
A good article. Blink, I used DVDit Pro HD a little bit, long time ago and it was OK. I think CS4 with pop-up menus maybe the better app now in the pro-consumer price range. Probably John Cline has the most experience with Encore on the forum, his feed back about Encore could be helpful. Personally, I have been always impress with Sonic solutions over the years and I've saw Blu-print in operation about 9 months ago and it seen to be more production focus, The app use for menus and virtual JB for Blu-print is really cool, but its expensive too. I avoid BD video disk projects because of limited access to good tools, but I use BD for data a lot and use BD to transport video and data if diskdrives can not be shipped safety. But the pop-up menus in CS4 Encore, I may change my mind, again.