I have no experience with the 270WSM. However, based on the ballistics for this new round it will do everything that a 270win could do and more.
It really isn't easy to get a single cartridge to excell at all three tasks that you've mentioned. You will have to make some compromises.
For factory ammo I'd go with a .308. If yo're going to handload then .243, .260, 7mm-08 would all be viable options. Personally, I like the 7mm-08. The 120gr V-Max bullet is very accurate in my rifle and there are hundreds of quality hunting and target bullets. The perfect whitetail cartridge, but not excessively heavy for vermin. [img]images/icons/smile.gif[/img]
Here is a little info on the 7mm-08.