Ok so Eden has been announced in the sense of being at 'feature freeze' - from here, if it's not in the main git codebase yet, it won't make it - they will bug fix and then release, with new features now being pushed to Frodo.
The list of what's coming is not wonderfully exciting it's fair to say. I think this release is about the XBMC devs doing a fair bit of internal work in preparation for big things to come later - although it has to be said the lack of the new AudioEngine in this release (and thus HD sound support) is a big disappointment as for me personally this was the most interesting potential new feature. That said, it's not really that big a deal, I doubt in my smallish room and at the lower volumes I can watch (thanks to kids) that it will make much practical difference. So it looks like Frodo (at least) before the PVR, AE, binary add ons. But hopefully Eden will be a release that brings a lot of stability & polish to the table.
In the end I settled on Openelec RC1 on my Shuttle XS35GT and Openelec RC5 on my ASRock machine. Why? Well the NVidia drivers changed in RC2 and there were significant frame drop issues after RC1 with the Shuttle (ION2) hardware. Most of the RC2->5 changes weren't that functionally important so RC1 is the best solution for the Shuttle right now if smooth video is important to you.
I am looking forward to moving both machines on to Eden though. I believe a lot of smooth video work has been done by FernetMenta/SwissKnife and I hope that this is going to make it in...in which case hanging on to the old system won't be that important. Smooth, frame drop free video is the one bit of XBMC that remains noticeably worse than other players (be they popcorn type, or computer) - so it's one area that really needs some attention.
Some interesting things I do see coming:
New built in NFS support and path subsititution features (i.e. you can tell XBMC to look for a particualr directory or file in a different location, so remap videso34db.sql to nfs://user@password/directory/file, for example) should make it easier to set up NFS shares (which are so much quicker than SMB ones, especially with smaller file browsing like viewing photos as the overheads in NFS are much lower than SMB) - and also to make multiple XBMC machines use the same library - you can pathsubstitute the library file rather than using MySQL it seems. This is good as the MySQL stuff is not beloved of the devs (jmarshall hates it!) - and thus sometimes it breaks - sticking to the inbuilt library support, but moving it to your server instead of the local machine should give the same results as using MySQL in terms of shared libraries/watched ticks etc., but with less overhead and hassle.
Add on support has moved on quite a bit so should be a bit tidier in Eden as well, and it should be easier (with a variety of skins) to add some Add Ons right to the front page - I will be sticking Australian ABC News24 there, for example.
Integration of the files and library view makes a lot of sense, hopefully it works as well as it does in my imagination! This will stop a lot of people getting confused about the various entry points (i.e. 'videos' being separate to TV and Movies confuses a lot of novice users).
I am hoping the new 'dirty rendering' based GUI rendering will speed up the skin processing on ION2 which is noticeably less smooth than on ION1 (with precisely the same skins and other hardware, e.g. SSDs etc). ION2 is just not quite as buttery smooth. Not a big deal, but one would imagine the lower CPU/GPU use would help in this regard.
Now - Openelec is in a funny state right now - post RC5 there has not been much public action and they have two main chains of development running in the background now - one on Dharma heading to the 1.0 release (or RC6 I guess) and a new Eden chain. It's hard to be that interested in the Dharma Openelec anymore, so I imagine I will be mucking about with the Eden development version of RC6 and hope to find a quite stable one to settle on around the Eden release. I will probably also experiment with the Live and/or Freak releases as well as Openelec again, to see which is the nicest/most stable on ION hardware.
It will be an exciting and busy time again, as the releases roll out. Plenty of posts to come!