I am extremely excited about this new vain of "reserach" that i've found. Collecting and Analyzing/Visualizing personal data. I'm also writing this post because I've run across enough websites and services that I want some kind of reference so I don't have to remember all of them.
First, I found your.flowingdata.com. I've looked into this the most so far, and have only glanced at other services such as daytum.com, and grafitter.com. There's a couple of characteristics which will shape my decision as to which service(s) I want to use.
At one end of the spectrum of personal data collection, we can imagine a 1984-like deal, where it's completely open. On the other side, you can authorize everything. It seems that these services have started from the authorization side of things. It seems that a big part of this competition is ease of use... then visualization. We'll see - I've only been at this for a bit (couple hours now). See, I could've logged that time, but it's just not convenient enough yet.
Similar data sites:
Pick o' the Post #4: "Up from the Skies" by Jimi Hendrix on Axis: Bold as Love