[tor-talk] Importance of individual useragent items

[Joe Btfsplk]

I noticed there are at least 2 different references in Torbrowser for 
useragent over ride strings.

The Panopticlick site picks up this one: "/Mozilla/5.0 (Windows NT 6.1; 
rv:24.0) Gecko/20100101 Firefox/24.0/," though there's another shown in 
about:config: extensions.torbutton.useragent_override;Mozilla/5.0 
(Windows NT 6.1; rv:17.0) Gecko/20100101 Firefox/17.0.

Aside from the fact there are 2 strings shown in about:config, the 
string that Panopticlick detects shows Windows 7 (32 bit - I assume).

Several Windows usage by version sites show Win 7 64 bit as much more 
common.  If true, why doesn't Torbrowser use that in its useragent?

The string in Torbrowser may be one of the most common setups? Some 
"useragent info" sites show 64 bit OSes are more common in the string.   
In my 1st visit to Panopticlick in a long time, using Torbrowser - it 
showed

Browser Characteristic:  User Agent
bits of identifying information:  6.73
one in x browsers have this value:  105.86
value: Mozilla/5.0 (Windows NT 6.1; rv:24.0) Gecko/20100101 Firefox/24.0

For the useragent string alone, 1 in 106 is pretty low.

A "test" for one of THE currently most common useragents shown on some 
updated lists of common useragents   - in vanilla Fx:
general.useragent.override;  Mozilla/5.0 (Windows NT 6.1; WOW64; 
rv:29.0) Gecko/20100101 Firefox/29.0

showed on Panopticlick that ~ 1 in 350 or 360 browsers had that 
useragent.  Still not bad, but 3.5 x the estimate for Torbrowser's 
useragent.
*That value could be skewed* by fewer or more Tor users visiting 
Panopticlick than Vanilla Fx users.  Still interesting.

One statistics site, 
http://store.steampowered.com/hwsurvey/?platform=combined, shows Win 7 
64 bit usage far exceeds the 32 bit, by 4.22 : 1.
Note: must allow js for steampowered.com; to expand the statistics line 
items (shown below), must allow js for steamstatic.com.
The values are for "usage" as of May 2014;  Unsure where they get 
statistics.  The +/- values are change in percentage, since???
Another "pretty" site, for all kinds of computer hardware / OSes / 
browser share, is http://marketshare.hitslink.com.  I'm not affiliated 
w/ either site in any way.

Windows 7 64 bit
50.53%
+0.51%
Windows 8.1 64 bit
15.34%
+1.44%
Windows 7
11.97%
-0.40%
Windows 8 64 bit
8.47%
-0.39%
Windows XP 32 bit
4.61%
-0.78%
Windows Vista 64 bit
2.20%
-0.07%
Windows Vista 32 bit
1.16%
-0.03%
Windows 8
0.45%
-0.04%
Windows 8.1
0.41%
0.00%
Windows XP 64 bit
0.30%
+0.01%