I think the two google tools in this exercise have great value. Google doc can be used to follow how students progress on a project over the course of a semester or unit. It can also be used between collaborating teachers that are designing a project. They don't have to be sending email attachments back and forth to each other, they just work on the one document they have saved and can make changes to it while they improve the project. The only drawback might be that since its available to everyone, it can be messed with by unscrupulous miscreants (or even by computer illiterates that don't realize what they are doing), sort of like how wikipedia entries should always be taken with really large grain of salt since anyone can add/edit info and make false statements that others might take as true.
I think google reader can add to the benefit already received from posting comments in blogs. It provides a quick way to get information fast. You don't get all the extra stuff that comes with websites, such as ads, and pop ups and other junk. It's sort of like the quote from Sgt. Joe Friday in the old TV show Dragnet: "Just the facts, Ma'am". The reader condenses the info down to just want you want. My reader now includes the blogs I'm following, in addition to those I added last summer in the 23 Things to Do project.