Wifi + apps for sales force ?

After seeing those IBM commercials where the guys are all over the
world,
and making changes to their biz...... how is it in the real world ??

One of the folks at work is scratching his head
about wireless and PDAs -
What are other real world compnaies doing with wireless technology ?
what kind of applications used
what kind of platform - PocketPC/PDA, Palm, Blackberry, Cellphone, ?
who will get it deployed, how and where will they be able use it

tnx -