From a very quick look I think the cheaper basic droplets have gone up 20%, but larger ones (such as the "general purpose droplets") have only gone up as little as 5%.
Edit:
Yes, it's only "Basic" droplets that have gone up 20%, everything else is only 5%.
I actually got slightly burned when they did that update. I was doing deployments by "slug" (their term) and the old slug went up to $10/month when they created the new 1GB $5 droplet option. Now my system double checks the price before deploying a droplet.
Edit: Yes, it's only "Basic" droplets that have gone up 20%, everything else is only 5%.