Do you have more details on your code coverage tests? You should also try running them with the tests in LayoutTests/fast/js, because typically all new tests are found there. I would be interesting in seeing what is missing so we can improve test coverage. I haven't had time to look at the tests in WindScorpion, but we aren't necessarily aiming for coverage in our performance tests. There are some things that are rare in real code, and we intentionally do not measure their performance in SunSpider. That being said, there are some gaps in SunSpider, and any attempt to round it out with some more tests is appreciated. You should probably talk to Maciej about that. Cameron