With the exception of a decent office package (word, excel, powerpoint), my handheld IS my mobile solution. I've often thought of getting a laptop, but at this point it'd become nothing more than a mobile gaming platform so that I can play ghost recon or UT2003, or maybe even Tribes2 (or 3 - Vengeance). But still. For work and productivity, my handheld is lighter, faster, and cheaper. /shrug/
Now if only the PPC platform can get a good office package to go with the Database solutions that are out there (HanDBase is pretty good, and I've only minor complaints but that is neither here nor there with this thread). The office package is what is going to really make or break the handheld taking over as the defacto Laptop replacement, for the simple fact that people want the option of using Word, Excel and PowerPoint without having to worry about crap getting stripped out of the documents just because the handheld version is too cheap (or not powerful enough) to handheld things... like tables.
Antoine is right though, also. From an IT Support perspective, it *could* be a nightmare. Things to consider would be putting a firewall and antivirus solution onto the handheld, strict policy guidelines on how to deal with corporate data (and contact lists, which in and of themselves is a virtual gold mine to some competing corporations and head hunters), as well as allowing for how to encrypt said data.
The ability to remote admin a unit, especially if the device is lost would be especially nice. To have a remote controlled "self-wipe" key that can be dialed up and sent would be especially protective. Then the only thing would be to ensure that nothing is kept on SD or CF cards as protective wipe measures wouldn't necessarily kill those.
It'd be interesting, wouldn't it? I'd LOVE to get on the team to craft those things and to help test them out.