The smaller screen and the smaller battery are most likely because Nokia wants to make the device smaller (and not the cost aspect, let us see about the price when it becomes available).
High-end Smartphone users expect a device the size of the N97/3GS/Pre . The previous tablets are too large, so Nokia would risk alienating a lot of High-end smartphone fans.

The software platform is new for most phone users, so Nokia probably decided to make the hardware as familiar as possible in order to ease the transition to Maemo.
I think that is smart move.

What I would like to know is if the device has a compass.
I also would like to know if it is an OLED or LCD screen and how well it functions in bright light (I think the nokia 5800 is often hard to use outside).

Maemo has A LOT of advantages over the Palm Pre and Andriod OS's. Maemo comes a lot closer to a full linux desktop operation system. Porting applications to maemo is relatively easy. Android and Pre are either locked, or you miss a lot of libraries.
People that start out with linux will be able to use these skills in Maemo directly and have a lot of powerful tools with relatively basic skills.
What was holding Maemo back was that the N8x0 devices were not powerful enough and that Maemo wasn't mature enough (some buggy software especially in the 2005/2006/2007 versions and a lot of apps breaking with new Maemo versions).
But because of the similarities of Maemo to full GNU/linux desktop environments and the capabilities of the OMAP3 it has to potential to take off real fast and have more apps, more possibilities and more developers than any other mobile platform.

I think that in the end the platform that has most applications available will become the dominant OS in the Smartphone market (that is what happened to the Desktop with MS-DOS and Windows in the late 80's/early 90's). I think Maemo has a REALLY strong position and could become that platform.


I really can't wait to see this device for real!