Nokia is currently considering extentions to the MIDP standard, particularly in the area of games, for first our products. Details of any such extentions would be made available via Forum Nokia when there is API documentation ready.
Nokia is very committed to open standards. Nokia will support JCP
specifications when there will be appropriate and finalized APIs available from that work. Currently we are active, for example, in MIDP NG and
CLDC NG specification work.
Well, I never heard about one Motorola phone with a Game API. They have so far followed the standards 100%. No special API's for graphics nor sound
Siemens got a Game API on the black and white devices (I designed and implemented it with one of the guys from Siemens) and with their new color phone (S55) you have a API that is close to MIDP 2.0.
I belive that Nokia will implement MIDP 2.0 at some stage (I see no reason why not) so that will help. After the JSR 118 (MIDP 2.0) was closed we found that the game API was not 100% good enough. But that is always the way.
Until then I suggest you use the Nokia UI API which is pretty powerful, only one problme, if you want to do a tiled background, then there will be a good over head compared to Siemens. But you can get around that anyway (will cost you memory).