I have signed up for Summer 09 pre-release.
Since preview release note mention that latest force.com IDE (summer 09) can now work with Eclipse 3.4 as well.
I did install Eclispe 3.4 and installed Force.com IDE plug-in.
But I can fetch only 15.0.2 (Spring'09 April 2009 release), using http://www.adnsandbox.com/tools/ide/install/ as the remote site for fetching new release of the plug-in.
Appreciate if you can guide as to whether I need to continue using CONSOLE for all development in Summer 09 pre-release or I can test latest force.com IDE features (which is now Eclipse 3.4 compatible) as part of Summer 09 release exploration.