The thing with JAVA is that is in principle ALL STANDARD all over the world, and we will be using standard architecture and JAVA SCRIPTING LANGUAGE like Groovy to make the GADGETS to work simply and make development a lot easier for JAVA DEVELOPERS. Im nos saying COMMON people will write gadgets, as the same happens in Joomla, only experienced PHP developers undesrtand Joomla so I dont think this will be aproblem for developers.
I have used Joomla for 5 years now we know it and we support it. But when we put it in a web site called www.iess.gov.ec the social security portal of our country simply could handle massive transactions. We used in that time DOT CMS and we had not even the slightest problem.
We will be releasing a Working Alpha version this January and I invite you to try it and make comments about it !!!