It's always important to know for developers what browsers they are developing for, who dominates the market, and what the current trends are.

I have gotten my hands on the Plaxo.com visitors' browser stats for December of 2009.

This information is valuable because Plaxo has a relatively general demographics, as it's not a site only geeks or only moms visit, and the statistics tends to not be skewed. Therefore, as you can see, Firefox doesn't occupy the same share as you might see on a techy site (on this site, more than 50% of users visit in Firefox).

Also, since Plaxo has a couple million monthly visitors and therefore a couple million data points, statistically speaking these numbers are relatively accurate.

Without further ado, here is the data, with some spiffy charts.

Overall Browser Breakdown For December 2009

Internet Explorer Version Breakdown For December 2009

Some numbers here have a value of 0.00% which means they've been rounded down and have really low numbers. The order is still correct though.

Firefox Version Breakdown For December 2009

Thoughts

• Internet Explorer is doing remarkably well – it is still most definitely the primary browser, so testing it should be planned accordingly.
• Internet Explorer 7 is by far the most popular version with 65.9% of all IE versions, followed by IE6 at 17.2% (wtf??), and only then IE8 at 16.9%. This definitely came as a surprise to me – both in how popular IE7 still is and how pathetic Microsoft's efforts to upgrade Windows users up from IE6 have been.
• Safari and Chrome are neck and neck at 6.20% and 4.6% respectively, with Chrome gaining rapidly.
• Opera is doing undeservedly badly – 0.6%. That makes me sad.
• IE 999.1? Interesting. I wonder if it's some sort of an uber hacked version.
• And, instead of conclusion: damn you, IE6! Why can't you die already?

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