Using "four major ranking" companies for websites, ProGenealogists has come out with the 2010 list of the 50 Most Popular Genealogy Websites
They show the rankings for 2009 and 2008 as well, and for the most part, the names are the same, it is only the order that has changed. There are some newcomers, providing resources it's possible some haven't seen yet. [I like the fact they know the numbers for 2008 and 2009 for the newcomers, indicating they have been recording the numbers for far more than the Top 50.]
USGenWebArchives is marked 'new' appearing for the first time at #8. (However, this isn't entirely new, as USGenWeb is listed as having 'dropped' off the list, from #30 last year.)
Other sites new to the Top 50 list include:
FamilyLink at #2 (up from #80 in 2009)
GenealogyBuff at #27 (up from #134 in 2009)
Archives at #41 (not ranked in 2009)
There are more new sites...visit the list to see them.
I was somewhat surprised to see that Footnote dropped from #9 to #37. It was my opinion that they had been adding a lot to their archives in the past year. There were a couple of other websites in the top 10 last year, that are below #30 this year.
All in all, a very interesting list, and I look forward to seeing what happens in 2011. There are definitely a few websites on the list I need to investigate further.
I am also hopeful they plan to update their 2009 list of the 25 Most Popular Genealogy Blogs. I suspect there will be some newcomers to that list, too.