Hello,
Thanks for your comment. I'm from StatCounter and would like to address your concerns.
Weighting stats means that the stats are only as good as the weighting methodology used. If the weighting data is inaccurate or out of date, then it renders the data completely incorrect. For these reasons, we choose not to weight our data in any way and instead we report is as we record - other commentators can, however, weight the data as they wish.
I'm not sure why you think we only have data from 4 countries. We have a very large global sample size of over 15 billion hits a month. You can view the country break-down here: http://gs.statcounter.com/faq#sample-size