Short answer: I really like the new dash for the 360.
The old ‘blades’ system was efficient (excluding Marketplace, which got hugely unwieldy due to the amount of content) but about as attractive as the back-end of a donkey, and pretty confusing for a newcomer. The new, clearly coverflow-inspired aproach is infinitely more attractive and welcoming. Navigation is in essence the same as the XMB on the PS3, only transposed - i.e. up/down switches categories and left/right selects things within a category. I do think the new look is even nicer than the PS3 though, since the amount of box art and themed sections really makes it attractive and varied to look at.
Those worried about speed navigation should like the ‘guide’ - just pop it up and you basically have a new version of what you used to get from the blades before - only if anything it’s even quicker to use in my experience, since the interface is much cleaner and navigation is more direct now that there’s no need to have promotional material sandwiched in among regular options (since ‘new’ announcements etc now have their own section in the main interface, and also appear as extra pages within the various sections, nicely filtered based on what you’re looking at).
The avatars get most of the attention, which is understandable but really unwarranted, since it’s the main UI that deserves to be paid attention to. The avatars are of course just better quality Miis, and you use them probably about the same amount (ok, maybe slightly more if you use the Friends Channel rather than the guide). I found mine useful just from the standpoint of being able to generate my own unique(ish) gamertag picture at last. Those that think they’re a frivalous addition can just ignore them once they’ve picked a random one.
I take my hat off to Microsoft on this one. It’s clearly a product of the iPod generation and manages to pull off being approachable, highly polished and very functional at the same time. Good job.
Oh, and Fable 2 is definitely quieter and a little faster now I’ve installed it on the hard drive 😀