Make sure you can afford it - DynamoDB can get very expensive fairly quickly as data size grows. Admittedly I last used it over a year ago and for a small company - but eventually we had to pull the plug because of the high costs.

I'd recommend estimating how much you think it will cost you, and then 10X that value. If that value is going to be hard to cover, stick with something else. If you're working for a Fortune 500 however, Dynamo is very nice.