The first two surprises after my first 11g installation was the new location of alert.log file and AMM changed yet again. I didn't run 11g beta program, so the two surprises could be old story for many others.
Just in case you wonder where's my alert.log files and what is memory_target parameter. Check following two metalink docs for full explanation.
Automatic Memory Management(AMM) on 11g
Finding alert.log file in 11g