A couple of concrete things come to mind -

1. DO has no private network; all traffic between your nodes occurs via your public interface. In fairness, it looks like they're working on this (http://digitalocean.uservoice.com/forums/136585-digital-ocea...).

2. Linode's NodeBalancers are super handy if you need load balancing, and don't want to run your own. There are certainly some things I wish they could do (alerting comes to mind), but they're a heck of a lot better than running my own.