Originally Posted by ComPH

What type of commute are you going to do? How far, hilly/flat, road/off road, city/country, how much load? Without knowing more of a detail, the safest bet is steel touring bike (even an older one), IMHO. Road bike would be most likely second choice, but maybe hard if you need panniers or bigger tires, XC may also have problem if you need to add panniers, but either one can do, depending on your specific situation.