I imagine ISPs will start using these results in advertising really quickly. "Google rates us as Excellent for video playback. Compare us with your ISP! We're faster than 82% of ISPs in this area."
Google/YouTube speed ratings could very quickly end up being analogous to school rankings. You want to be in an area with good schools, and if you don't have good schools you're probably going to start putting pressure on people to improve things.
In the Boston area, one ISP already does this (for Netflix, at least). Not only do I get flyers in the mail, but they also advertise online[1]; though that page has been updated to highlight some new feature with TiVo boxes, it used to specifically mention RCN being the fastest ISP in and around Boston for Netflix. The page still does say "RCN is Optimized for Netflix: RCN is directly connected to Netflix, providing the best possible Netflix experience, including a better picture and faster start up times."
Actually a major ISP in France (Free.fr) is throttling Youtube, on purpose, because they believe Google should pay them for the bandwidth but Google disagree.
An easy fix is using a VPN, because then the traffic is no longer recognized as Youtube by the ISP.
The (pending) merger of Comcast and Time Warner does not change any areas from a choice of Comcast or Time Warner to no choice, because there are no areas where the two cable providers cover the same addresses.
Lack of competition and transparency in the last mile is the essential problem, but the Comcast/Time Warner merger doesn't really change the status quo there (unless someone makes a significant change a condition of the merger). The blueprint of a solution is the pre-2005 regulation of DSL by ILECs: make cable providers (or at least comcast), ILECs, and anyone else with a natural monopoly offer line-sharing on reasonable terms, and watch ISPs spring up (or re-emerge) with competitive offers and better routing than the incumbents. Bonus points if wholesale pricing is required to be at least as low as retail pricing, unlike in the DSL times.
If it becomes clear that areas served by a single ISP get worse performance than those in areas with choices, than that too is useful to know and promote, right?
Or maybe Google just wants to publish charts showing Google Fibre areas are consistently at the top of their lists so that other municipalities will want to make it easy for them to enter their local market (and/or ask their local monopolies why they can't be more like a Google-town).
"I don't know, my ISP requires me to buy the video sites package in order to show video on YouTube ... but the good news is, it would give me access to Hulu, Amazon Instant, and Daily Motion too!"
Google/YouTube speed ratings could very quickly end up being analogous to school rankings. You want to be in an area with good schools, and if you don't have good schools you're probably going to start putting pressure on people to improve things.