Mark, I have an IOIO board mixing an LX7007 Pro IGC and PowerFLARM Core, to a Dell Streak running XC Soar 6.5.

The answer to your questions, in my case - though I'm wired to the Android device not bluetoothing (once the connection is made, really to the user there are no differences) - a

1. On the map page - you see the FLARM targets and, IF you have installed the FLARMnet database for XC Soar (easy), you also see the contest ID (or whatever the FLARMnet owner has decided to put in - perhaps, registration). Page 104 of the 6.6.5 manual shows a picture.

2. To get more detail, when the FLARM radar screen appears (lower right corner) over top of the screen (so you may lose info boxes depending on your screen set-up), you tap it. It takes over the whole screen; you then get
Top left : If available the FLARM ID of the selected target.
Top right : Vario of the target, derived from the consecutive altitude
messages.
Bottom left : The distance to the target.
Bottom right : The relative height of the target, for the selected target.

You tap again to get rid of it and go back to your navigation screens. Pages 105-108 talk about and show pictures of this (manual at http://www.xcsoar..org/discover/manual.html).

I don't think the PCAS/ADS-B targets are passed from PowerFLARM; I don't know if miniOZ flarm does transponders/ADS-B.

For me, having the flarm take over the whole display is bothersome; even the small flarm radar screen is a problem, overlapping info boxes whenever traffic is displayed (where I fly, airspace is usually nearby). I will probably turn off the flarm radar screens, and just keep the map display of flarm targets. I have an external rectangular Butterfly display that displays flarm targets, climb rates on selected targets; a glance at that screen gets me the info I want, and keeps my head out of the cockpit for the large number of gliders around me that aren't flarm equipped. If you don't have space for a small display, the android display likely will meet your needs; if not, purpose-built flarm displays are fairly cheap.

Overall, for me it works very well; if I lose my Butterfly display in flight, I have a back-up, and get situational awareness of traffic around me on the XC Soar map. You do have to have a friend or vendor make an IOIO box if you are a techno-bozo like me (thanks again Luke). Dave indicates that the dongle will pass the flarm data by bluetooth. A neat solution.

So, in answer to your questions:
A flarm radar with registration and climb rates? Or just targets.

The answers a Yes (qualified, when you go to the purpose flarm screen), and yes (always, with contest numbers).

There has been discussion on why more tactical data isn't displayed on the main screen; the developers feel that more data would clutter the screen, and that the purpose of the flarm - anti-collision warning - is achieved by the current implementation, and it keeps your head out of the cockpit.

Hope this helps.