I think the reputation varies based on the school. If it's a brick-and-mortar school, like the ones mentioned in this thread – U of SD, LSU, U of MD, etc. – it's still pretty widely respected. Many (dare I say “most”?) MBA programs are online because the students are working professionals that can't guarantee they can leave work to attend class at a certain time every night. So, if the school is a brick-and-mortar school, whether the courses were taken online or not isn't always known and is even less likely to matter.
However, “online schools” like Phoenix do have a pretty bad reputation. Whether it's deserved or not is a separate conversation, but an MBA from Phoenix probably wouldn't carry nearly the same weight as an MBA from LSU, U of SD, or a face-to-face MBA of your choice. Again, I'm not saying this is or isn't deserved, but it's reality. Any of the schools that pop into people's minds as “online schools” do have a reputation that isn't as great.
There's a difference, though, between an online program from a traditional school and an online school. An online school may be the expert at presenting education online, so maybe Phoenix would have the best online MBA – who knows. However, I do think it's a fair general statement to say that a degree from Phoenix isn't likely to earn points with employers. But a degree from an online program from a traditional school is fully acceptable. The nearest face-to-face MBA program for me is about 2 hours away; the other colleges and universities in my area all offer online MBAs.
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