Since there seems to be a lot of interest in this, I created something similar on ericscc.com (not live yet) but I wanted to give a preview here and get some feedback.
I can do a line-type chart like Fred93's, but I thought another interesting aspect of this is to control for the loan age and look at how groups of loans performed when they were the same age. An example:

This shows how loans from various months were performing after 6 months of aging. The general trend appears to be downward - i.e. loans originated in Aug. of 07 were doing better after six months than loans originated in Dec. of 06 did after six months. Whats more difficult to tell though is whether this is because lenders are picking better loans, or simply because the credit grade mix is different (e.g. more AAs and fewer HRs). I suppose you could argue that these are the same thing, but I think it's more interesting to know if the average funded "C" or "D" loan today is better than the average funded "C" or "D" loan a year ago. Unfortunately there just isn't enough data to draw much of a conclusion yet (I've filtered the chart by credit grade and the results are just all over the place).
The actual URL for the image is:
http://www.ericscc.com/graphs/showLoanAgingGraph.php?age=6If you change the "age=x" parameter you can view the chart for however many months of aging you wish. Any feedback you guys can give me on what info I might add to that chart, filtering options, or any other data that I should show with the chart to help with analysis would be appreciated!