Practical Product Lines 2009
I just returned from the PPL 2009
conference in Amsterdam. Although small, the conference was very good: nice program, competent participants, nice venue, good food. I will definitely go back next year. It is also better value for money than SPLC if you're interested mainly in practical aspects of PLE.
To get an impression of what the conference was like, take a look at the Twitter #ppl2009 stream