As a gaming platform most 3g phones are capable of more intensive games than a Gameboy advance or Snes ... but what holds them back Java , the only language that works on most of these phones as a standard, Java's strength is that it works on Every OS , from Linux to Mac ,but it is slow and inefficient compared to C , basic etc.
Also the controls and screen on most mobile phones are much inferior to that of a gameboy , the buttons are much too close together on many models for the hands of an adult , also the screen is usually tiny....
Otherwise the mobile phone is the perfect gaming platform , everybody and their mom.. and grandmom have one or several , they come with bluetooth and wi fi capability ( multiplayer!) and colour screens , but sadly most of what we get for them are simple games like Snake or mario clones .
Also lastly they need a standard media to sell these games on , storage on most phones is limited to less than 10mbs , a complex game with high resolution sprites will take up much more , And to prevent piracy etc.
Lastly most mobile phones
So to become gaming platforms , phones need :
To use C , Python etc. as standards in all OSes.
More ergonomic controls
larger screens .
More storage , and / or a standard external media eg. mini disc, solid state memory card .
http://www.armadilloaerospace.com/n.x/johnc/Recent%20Updates John Carmacks blog , referring to phone games .
http://www.gamespot.com/mobile/action/quak...ile/review.html Quake for mobile phones
http://www.gamespot.com/mobile/action/duke...m3d/review.html Duke nukem for moble phones