Data Plans: Unlimited or 200 MB Per Month?

I just took this picture of my study space
to verify whether I will be able to take pictures with
my regular camera and post them to the blog since doing that
with my BlackBerry is something I can't
afford to do any more until
the end of the month

Spanish prof recently posted a question as to whether it makes more sense to go for an unlimited data plan on her smartphone or to choose the 200 MB per month option.

Phone companies tell gullible customers like myself that they really don't need unlimited plans and that all their data needs will be covered extremely well by the plans with pre-set data limits. AT&T has already killed its unlimited data plan (this is a company that is unstoppable in its desire to rip off customers), and now other companies are following suit.

As one of those idiots who fell for the "you-really-don't-need-an-unlimited-data-plan-because-you-don't download-that-much" mantra, let me tell you what the 200 MB per month means in practical terms. I use my BlackBerry's Internet access to read and answer emails, blog and Twitter. I never watch any movies or YouTube videos. Never download any music, games, or anything else that can be downloaded. Never surf the Internet from my smartphone. Maybe once every six weeks I receive a .doc attachment and open it. I also take pictures and send them to my blog once or twice a week. When I do that, I always make sure that the photo is emailed in the smallest size possible.

And still, somehow, I keep exceeding those magical 200MB all the time. And then I have to pay extra for the next chunk of data. Of course, if you use your smartphone's Internet access even less than I do, then, by all means, get the limited plan. The only question I have is why a person who uses it even less than I do would need it at all.