Roy Ganor, a committer on the Eclipse PDT project has written up a post from an insider's perspective on the whole thing and the path that led them to a stable 1.0 release.
Today the PDT project community consists of about 30 users that are daily involved, and about 300 users that are weekly involved, and about 13,000 users that are monthly involved in the project . Remarkable! by any mean of open-source project.
He talks about initial feelings about the move towards PHP, how the community grew surrounding the project and the level of integration that the project has with both the Eclipse software and with the Eclipse community.