The macs' glossy screens seem alright to me, I'm typing on one now and was a former matte screen zeolot. They don't reflect very much. They're quite usable even when you have an open window behind you on a sunny day.

If you want to develop on multiple operating systems, well, I recommend making sure you get a CPU with VT-d. If your current machine on which virtual machines are painful doesn't have VT-d, I recommend trying one that does. (And of course, get sufficient RAM.) VMs seem painless to me, at least on the machines with VT-d that I've tried, and somewhat painful on machines without VT-d. (I experimented on the same Thinkpad enabling and disabling it in the BIOS -- the difference was clear!)