Here is a list of some recent articles (last month and half) that I think are very interesting and I advice oracle developers and DBAs to read:
Concurrent Statistics Gathering introduces the Oracle Database 11g r2 latest patchset 18.104.22.168 new concurrent statistics gathering mode.
BTW I think 22.214.171.124 should have been 11.3 due to the addition of several features :-).
100 Things You Probably Didn't Know About Oracle Database series:
Part 1: Myth of Commit Causing Buffer to be Flushed to the Disk
Part 2: Myth: Oracle has a Central Locking System and it's followup
Oracle DBMS_SCHEDULER Part 1–The Basics: A good start for a series of articles about DBMS_SCHEDULER. This article make a very complete introduction to concepts behind this 10g feature that for many people is still a mystery.
And last oracle Magazine Articles:
Simulation Demonstrates Performance: it show the use a of new 11g r2 feature of the SQL Performance Analyzer (new in 11g r1) that allow to get statistics of how the performace would with Exadata;
Ask Tom column specially the about histograms entry