Google Analytics (and some log parsers) will give you breakdowns on usage of different browsers, different versions of those browsers and screen resolutions.
I'm just curious to know what SO users user. Any chance we could get some stats on that? You may view this as commercial information, in which case I understand (as i'ts relevant to marketing/advertising).
I'm also curious to know the # of users who read and/or post from mobile devices and if so which ones.
UPDATE: Please refrain from personal anecdotes ("I use..."). I'm interested in actual usage, not personal stories. Thankyou.