Why move to the cloud?
I Google'd "move cloud computing" and 32,900,000 matches came back in .15 seconds. So I'm guessing that anything I say has been said before, ad nauseum. And since I'm not really a tech guy (just enough to be dangerous) I can't really provide any technical insights that others haven't provided.
But, I am a business guy and I approve payments, watch the numbers, and know where the money goes. And when you start looking at it from that perspective, it starts making sense.
We started with a ton of equipment (servers, NAS', SAN's, firewalls, tape back-ups, RAIDs, etc.) that we had to buy and then we co-lo'd it in a third party data center, where we paid "rent" on a rack. With a hardware investment in the six figures, not to mention rack charges, a cloud environment can make sense, especially if you have large storage requirements.
So the moral of this very short story is run the numbers to fully understand the true costs of running on your own equipment (and don't forget to factor in equipment replacement every few years, maintenance, spare parts, internal charge backs, more storage, etc.) vs. the costs of cloud computing. You just might be surprised.