Subclipse D'oh moment on commit
2008 January 22
Did you know when committing in Subclipse, you can double click a resource listed and it shows a compare of your working copy and the repository's head version base revision? See snapshot below.

The compare is actually the equivalent of svn diff. Which means it compares your current changes with the BASE revision in the working copy. The HEAD revision in the repository could theoretically be different. Your commit will fail with an out-of-date error if this is the case.
This blog post has details on this and other features:
http://markphip.blogspot.com/2007/01/features-of-subclipse-commit-dialog.html