Ask HN: Pros and cons of various hosting providers?

Can anyone speak to the pros and cons of the current crop of hosting providers?

What I have in mind is pretty straightforward: a Java web-app with a relational DB back-end, starting small.

As far as I can tell, AWS is the standard solution. Heroku and Azure are both credible offerings, but they only support one database each, PostgreSQL and SQL Server, respectively.

Any other issues?