I just heard about this serious competitor (if don't need a keyboard)
which is based on another Linux OS (LiMo).
I wonder whether Maemo can be ported this device?
Here's the list of differences wrt. N900 which I could find:

+ 115.8 x 58.0 x 12.9 mm @ 134 g
+ 3.5" AMOLED 800x480 display
+ capacitive multitouch display
+ 1500 mAh battery (500h standy, 6h talk)
+ high-quality and robust build
+ HD video 1280 x 720 @ 25 fps
+ FM-reciever, proximity sensor
+ SAR only 0,4W/kg
+ Opera 9.6 browser
+ available NOW!
+ price w/o contract ca. 350 EUR in Germany

* LiMo (Linux Mobile) OS
* TI OMAP 3430 600 MHz (same as N900) CPU/GPU chipsets
* 5 Megapixel autofocus camera (2560x1920) + frontal VGA camera
* 16 GB internal flash, SDHC card slot

- no physical keyboard
- no IR, TV-out
- only Bluetooth 2.0
- dual band UMTS (900/2100Mhz).

and some links:
http://samsungh1.com/samsung-h1-specs/
http://www.geeky-gadgets.com/vodafon...der15-10-2009/
http://shop.vodafone.co.uk/shop/mobi...360-samsung-h1
http://www.inside-handy.de/handys/vo...bericht_1.html

first users report that you would need to get used to the software
but they're exited about the hardware.