It is NOT normal in any other car. Well I take that back British Leland with cork gaskets seemed to leak every time I adjusted the valves. I always replace the with a valve adjustment. Modern cars with valve cover gaskets made of quality material run over 200,000 miles without any problems. Our car has a man made gasket so it suffers from human error, quality of work and poor design.

In my opinion, it is just a matter of time before all crossfires suffer this. I have friends with Mercedes SLKs and they have the same problem and they paid alot more for those cars. Unless you like cleaning your engine, take it now and get it fixed. You may want to remove the air cleaner cover and take a look at it from both sides. It has been my experience the drivers side always leaks after a period of time. I check mine every 3 months or so.