I would like to talk about Maemo / Meego (Nokia for Linux Mobile PCs). While it is in transition, and currently Maemo 5 has only one good phone (and some cheap Chinese), but I feel that it will become big soon (I like that many people think that Meego will become Nokia high strategy end and Nokia is the largest handset manufacturer in the world). In addition, the N900 is the coolest phone.
And theirs is basically an open source Linux device (pretty similar to standard desktop Linux). The idea of QT Creator is excellent and cross-platform (comes with a built-in visual designer and a beautiful documentation buffer), but you do not need to use it, there is some support for using your own text editor or idea.
There is no signature of key nonsense (I did a student project for a blackberry and was very annoyed with the keys). Other things that I didn't like about the blackberry module: windows only eclipse, our team had a lot of problems when we figured out how to add third-party libraries to COD archives on a blackberry. In addition, some of the classes are somewhat rare in many ways, especially String / Char, perhaps since I created it on the basis of ME, I also did not like the read / write apis file, it was somewhat inconvenient, perhaps, since Blackberry applications only recently Got the ability to store files (before you could store or retrieve objects to disk through the persistence layer).
Preferred languages are (Gobject C at present, but less for Meego), Qt flavored C ++ and python. The libraries are good there, and qt is especially well documented. Since it has a tiny Linux module that you can use when debugging a device (there is also an emulator).
Note. I did not develop anything for Maemo / Meego, but I read a lot and just fell in love.