How well do you know the potential new company, potential new coworkers? How much support and buy-in does this team-building effort have from management and executive concerns in the company? Are other people happy there? Does the company send people for training? To conferences? Do they bring trainers in-house? Are you going to be working with competent and capable people? How up to date is their software? Hardware? Office furniture? Copiers? If stuff is dingy, old, falling apart, these are probable red flags
10% more money and significantly less commute time is a decent improvement, especially if it also means you broaden your skillset -- but you have to enjoy the new challenges put before you, or it will be tough to succeed at them and even tougher to be happy in your new situation.
You really have to change jobs every now and then, particularly in technology, in order to have the opportunity to land the really cool jobs AND get paid top dollar or doing it.