We have implemented some changes to the scoring mechanism.
First of all, now the challengecount is incorporated into a sites score. So sites with a lot of challenges will score higher. This is so that the difference in points per solved challenge doesn't differ so much between sites anymore.
The second change is in the users scores.
Scoring high on a single site now scores a lot more than scoring low on a lot of sites.
So to boost your score you can work on some of those harder challenges on your favourite sites in stead of doing a few simple challenges on a new site.