Java EE application servers increase their feature sets (APIs and administration features) whilst business applications get smaller and smaller. This introduces a new issue: if you need a single feature of a new application server version you'll get a complete package of features that you didn't need in the first place (the snowball effect). Let me give you an example: in WebSphere 7 IBM provides a high speed integration adapter for IMS assets. We need that, but we don't need all the rest that gives us a headache in terms of migration efforts. Now, if the amount of APIs increase in Java EE with every version, I predict that this problem starts to get more and more complicated. That's a reason why I don't appreciate the fact that Java EE standardizes former framework functionality like dependency injection (CDI). Business applications may get smaller, but application server feature sets get huge this way. Is that a good trend?
I typically try to keep application bundles small in my business applications. Not in size necessarily but in terms of packaged features. This way I don't create artificial dependencies. You need to deploy a new web service version? Then I can only deploy that specific web service module without creating a snowball effect of additional required deployments. Small packages reduce the need of branch development. Small packages reduce the risk of instability. Small packages reduce the necessity to synchronize deployments of different development teams. If you finnish your work or you need to deploy a new version of your application then you should create as little dependency as possible. In an ideal scenario you don't need to talk to any other developer if you want to deploy the features your responsible for. I think this should also apply to application server software. The trend to shrink business application feature sets and increase those of application servers should stop. Or: administration features of application servers should be seperated and compatible to the different Java EE standards. A more moduralized approach would be desireable.