With TechCrunch having just posted an article on this matter, I thought I'd add my take on it.
An MBA offers a variety of benefits, and many people, in discussing this question, just focus on the education. The problem with that is that formal education is an incredible inefficient way to learn. Think back to the 40 or so classes you took as an undergrad. How many of those really made a difference in your life? Couldn't you have learned just the most valuable stuff in a much shorter amount of time? Of course! Yet people would rarely conclude that undergraduate degrees are a waste of time. Note: this applies also to computer science degrees. You don't need a full degree to make you a great programmer. Why then do so many people argue that entrepreneurs should have CS degrees over MBAs?
Like undergraduate degrees, MBAs offer a lot of value beyond the learning. You meet people who mentor you, and you mentor them. You gain lifelong credibility. You gain a lifelong alumni network, offering many many thousands of people who will answer your phone call just because you went to the same school. You can't get these things from a textbook or from reading some "MBA 101 blog."
Is an MBA right for you? I have no idea. There are no credible studies on this, since you can't exactly do a controlled scientific experiment. And the vast majority of people will just tell you to follow in their footsteps.
Here's the advice I will give to prospective MBA students:
- Name Matters: The amount of credibility and the quality / reach of the alumni network varies with the name / rank of the school. There are a lot of people for whom a Tier 2 MBA program will add substantially to their life, but there are also a lot of people for whom it won't. In short: don't just go to "any" MBA program. Go to one that is a "step up" from where you are now.
- Know What You Want: MBA programs are only two years, and you give up a lot in the short term - personally and professionally - to attend. If you enter knowing what you want, you'll be able to seek out the right people and opportunities much more quickly.
- Field Expertise Matters Too: An MBA will probably help you run a better business, but so will many things. Considering padding your MBA with a bit of field expertise, whether that's a tech skills, retail experience, medical background or whatever. The ultimate for a tech start-up is a business skills + tech background + industry / market experience.
And, of course, remember: if you're considering an MBA, you'll probably be just fine whatever you do. Don't stress it too much.