1) Get trunk ready & tested

2) Find and replace all the version numbers in the file headers and
the VERSION constant (be careful not to change the previous version
names in the changelog in the readme.txt)

3) Leave 'stable version' as old version in readme.txt (although other
changes to readme.txt should have been made)

4) Check in trunk

5) svn export trunk tags/newversion

6) Check in new tag

7) Go and edit readme.txt in the trunk and in the tag so the 'stable
version' is now the tagged release (and the readmes are identical)

8) Final checkin to update the two readme.txts

9) Wait about 10 minutes