Wow! Is this new, or has it been out for a while? Just finished reading Steven Levy's book on Google - amazing read and insight into Google's history.
I was consulting it back in March 2013 for details I could use for my http://gwern.net/Google%20shutdowns so I know it goes at least that far back.
But you can also punch it into the Internet Archive (http://web.archive.org/web/20120401000000*/http://www.google...) and see that it goes back at least to March 2012. As it happens, as part of the previous research I know that a lot of Google content moves around various URLs without redirects, so between that and how the first IA version is comprehensive, I strongly suspected that it was much older than March 2012; one useful trick for finding the original URL is to look for quotes of the page on other websites which point at a different URL. In this case, if you quote the bit starting with "Larry Page and Sergey Brin meet at Stanford...." (the first entry) and you search in Google with a date-limit of 1995-2010 (in the 'Search Tools' option), you can see hits dated from 2005, 2008, & 2009. The 2005 would be best, but it's some sort of spammy junk, so I try another hit, and it links to 'http://www.google.com/corporate/timeline/#start' which is quite different. That takes me back to August 2008: http://web.archive.org/web/20080401000000*/http://www.google... We can't search for this because it's broken but it tells us that we can narrow our timerange even more, to early 2008. Another hit includes a 'trackback' link to another Google URL, which I duly load up: http://web.archive.org/web/20020223143331/http://www.google.... Useless, since it's not the timeline - but notice the sidebar! 'Timline', bingo. Now we can go all the way back to December 2001: http://web.archive.org/web/20011213165211/http://www.google....
So, this page was started at least as early as December 2001.