Some decade-end lists to consider for the spreadsheet:

Alternative Press
http://thruspeakers.wordpress.com/2009/11/18/alternative-presss-100-best-singles-of-the-decade/

OUDaily
http://oudaily.com/news/2009/dec/08/decades-best-singles-2000s/

Pretty Much Amazing (US)
http://prettymuchamazing.com/music/best-songs-of-the-decade-2000-2009

Starpulse
http://www.starpulse.com/news/index.php/2009/12/15/the_ten_greatest_songs_of_the_decade

Boston.com
http://www.boston.com/ae/music/gallery/rodmanbestsingles/

Herald Sun
http://www.heraldsun.com.au/entertainment/music/cameron-adams-judges-the-hits-and-misses-of-the-last-decade-do-you-agree/story-e6frf9hf-1225815030639

Hitflix
http://www.hitfix.com/blogs/2008-12-6-the-beat-goes-on/posts/who-tops-our-best-of-the-decade-album-and-singles-list-beyonce-justin-jay-z

Euphorialand
http://euphorialand.com/2009/12/23/the-best-200-songs-of-the-2000s-decade/

Telegraph
http://www.telegraph.co.uk/culture/music/rockandpopfeatures/6198897/100-songs-that-defined-the-Noughties.html

Chicago Reader
http://www.chicagoreader.com/TheBlog/archives/2009/12/31/mixtape-for-a-low-dishonest-decade

Drowned In Sound
http://drownedinsound.com/in_depth/4137653-ninety-songs-of-the-noughties-dis-editors-picks-p2k-alternative

The Larry Page
http://www.thelarrypage.com/bestsingles2000s.html


Noise Addicts
http://www.noiseaddicts.com/2009/12/20-best-music-singles-of-decade/

Orange County Weekly
http://blogs.ocweekly.com/heardmentality/top-10/top-10-songs-of-the-decade/

Perth Now
http://www.perthnow.com.au/entertainment/the-top-50-songs-of-the-noughties/story-e6frg3i3-1225805474456

CBC News
http://www.cbc.ca/arts/media/blogs/popculture/2009/11/sounds_of_the_times.html

Fishpork
http://fishpork.com/tag/mgmt/

I was looking at Pretty Much Amazing- that site would meet the Alexa traffic ranking criteria- and, it does have a collaborative team (with one guy running the site and contributors). So that may be eligible.

The Telegraph list was deemed not eligible, because it's not really about the greatest/best/most important, etc. tracks- rather the ones that defined the decade- a fine line in the differences for criteria.

Something like the Herald Sun is just one critic, so that wouldn't be eligible. Single-critic lists like Robert Christgau would be eligible.