The URIs for those sites will need to be changed for every version of scala. But, since we only will support 2 versions of scala at any given point in time, may want to consider names such as 'dev' and 'current' which identify their version unequivocally (resp. 2.9 and 2.10 for now, 2.10 and 2.11 later, etc) .

Your PR will probably pass without that, though.

The same goes if you decide to support a second version of eclipse, with the recent developments over juno: your choice to generate one site for each build simplifies the task dealing with update sites (i.e. you don't have to merge them), but you may have to update your pointers.

If you want some insight on how to (at least) simplify your build process (so that a new version does not require you to update verison numbers all across your build profiles and URLs), you can look at the [play2 plugin](https://github.com/scala-ide/scala-ide-play2/blob/master/pom.xml)  : it also generates several websites, but its URL is set as a function of the various version variables.