Play 2.0 is a high-productivity Java and Scala web application framework that integrates the components and APIs you need for modern web application development.
I like Play's view engine that's looks like the ASP.NET Razor engine. I don't like the fact that Play largely ignores existing Java EE APIs (except JPA) and I like it even less that they (seemingly) switched to Scala on a whim, since at the time that was the most hyped language around. Will they move to Ceylon next when that happens to be the most hyped language at the time they'll be planning for Play 3?
Upgrading hasn't been a really fun experience either. Now, it most frameworks something breaks when you upgrade, but Play has been exceptionally bad here. I haven't used 2.x with Scala yet, but the 1.x Java version suffered from high memory usage and slow startup time. Now again, with most frameworks these days startup time is increased when the app gets bigger (mainly due to annotation scanning), but here too Play behaves a little on the extreme side. Again, this is for 1.x, perhaps 2.x is better.