the new sidekick will most likely have both 3G and a touch screen. the OS will definitely look different so it can be finger friendly and the fact that now microsoft owns it. they'll prolly put in a zine player and nice internet. and in order to have a good browser it must be fast therefore it will have 3G. many people (including myself) that have a sidekick hate using the internet since its so slow. the keyboard probably wont change much, maybe some cosmetic changes, but all in all the keyboard on sidekicks is great, minus the slide.
if it includes a touch screen and its made by sharp, it will have a nice screen. the phones sharp make for the asian market have exceptional screen quality. one even has a higher resolution then the touch hd.
im sure the new sidekick will be great.