I've finally managed to get it running on my new Windows 7 64 bit laptop, but that was only after fiddling with the pre-release version and having a few other semi-related difficulties.
I've gone with Glassfish as my HTTP server, using Oracle Glassfish Server 3.0.1
There is now a dedicated OTN forum for the Apex Listener, and I've added forum entries on these problems - which I'm sure along with other little nagging things - the Oracle development will get onto with Glassfish as time goes on.
1) My URL to open Apex Builder requires the slash at the end, otherwise no deal
2) Unfortunately when I try to re-visit my listener configuration page
I get the following error
/apex40/listenerConfigure//index.jsf not found
I'm fairly happy with the set-up, it was relatively easy to do in the end and the new documentation accompanying the release is vastly improved - but Tomcat is no longer supported, only OC4j, WLS and Glassfish.
So now to continue exploring Apex4.0
I must say I'm coming across some improvements to the documentation. Apparently when creating new workspaces for existing schemas, Apex4.0 no longer grants any roles.
From there I noticed that there is a new glossary describing item types. I think this along with the Available Conditions appendix is the sort of documentation that is needed to assist people new to Application Express - that and the context sensitive help within the builder, that is sometimes a little lacking.
I confidence that over time, like all Oracle products, this will improve. I wonder what they're thinking about for the next release...