With the wide range of opportunity available to obtain an online degree, it almost doesn't make sense to go to a university or college. Of course online courses will never be able to match the full immersion that an actual insitution can offer, but for someone who is working, or tied down with other commitments, it can open doors that where closed before.
Whether you need to upgrade your education for a promotion at work, or to even just get the job that you want, an online education might be right for you. It's generally more affordable and most importantly flexible then a competing course at a university or college.
Online universities are striving constantly to become more reputable, and to offer courses in competitive fields. Keeping that in mind, the entrance requirements are typically the same for both online & offline.
A typical online degree can be completed in about 3 years, but of course that varies on how much commitment you give to the course, and also if you have any previous credits that are applicable. One of the most important things to do when considering out on the path of an online education is to do your research! Research both the history of the school, as well as the current reputation, and if the degree you will obtain will be recognized for what it is you need down the road. There has been instances in the past where some online institutions have basically just been selling degrees, which can lead to several problems such as: Loss of jobs, and involvement with authorities.
Keep a level head on your shoulders, do your homework, and you will make out just fine!