what I learned from above video: possible 2nd half with extra battery, camera flash, you name it...as long as 3rd party developers see cash in it it may come available.
And since even for N900 the most diverse peripheries have appeared (game grip, mugen battery etc..)
I consider this good news for our hardware keyboard.

Other bits from that video: actual screen will be larger (indeed) phone will be thinner (sigh...why.. It looks pretty outdated already.. give me IR and FM in the standard half, ok.)