As of april 1st, Oracle XE 11g (11.2) beta is available for download on OTN.
From the installation guide: RAM (SGA+PGA) still cannot exceed 1 gigabyte, but maximum userdata has been increased from 4 to 11 gigabytes!
Also included is the 4.0.2.00.08 release of APEX so you can start building your applications right away.
It looks like the database management features which were part of the default Apex 2.1 installation on 10g XE is skipped (for now), but you can view your parameters and sessions navigating to http://localhost:8080/apex/f?p=4950.
For a complete list of (un)available features see the licensing information document.
Feedback and comments as well as issues can be reported in a separate forum: http://forums.oracle.com/forums/forum.jspa?forumID=1378
Oracle XE 11g beta available,