There were several reports of problems with initialization of Android plugin in NetBeans BugZilla. Thanks to our friends in NetBeans team an email about this ended in my mailbox. Fix is on the way to the update center.
The problem affected people who (re)moved Adroid SDK from a location specified in NetBeans. While the original code was OK in the past there was a small change in SDK libraries (RuntimeException is thrown where IllegalArgumentException was used). It is covered with a test now to avoid surprises like this.
Did I write that the only way how to convince to contribute larger chunks of functionality again is to sent a donation? I like it that there are 10.000+ downloads but this doesn't justify my time spent on this. Keep in mind that Eclipse plugin is developed by Googlers and we do not have any sponsor like this.