There are also Windows Mobile phones on Verizon, like the recently announced Samsung Omnia i910 and the HTC Touch Pro. With those, you'd be able to continue using your existing software.
You can view but not create Word docs with the Storm out of the box. If you uprade the Documeents to Go on the device to the Premium version you can create Office documents as well. It works just as well as Word Mobile on Windows Mobile.
For the medical reference(s), check the web site of the folks who make it to see if they make a BlackBerry version. Windows Mobile has the largest selection of medical reference applications, followed by Palm OS, but there are some for BlackBerry OS.
The Storm makes a very good mobile music player and you can use microSD cards to carry a large selection of tunes with you in the car.