Bilgefisher/Dan,
I asked this question to Joe Toms, the chief investment officer at Prosper last week. Because I have noticed the continual reduction in available repeat borrowers. I was investing in 12- 15 repeat borrowers a week in October and November and now two weeks into February I have invested in exactly two this month.
What Joe said is that they promoted heavily to repeat borrowers in the last quarter of last year and most of the people who wanted a loan have already taken one. Now, they continue to promote to most borrowers with a good payment record once they are six months into their first loan but there are fewer of those when you compare that to the whole platform.
If you look on Lendstats you can see that the total percentage of repeat borrowers have dropped dramatically. From 36% of all loans in the 4th quarter of 2011 to just 22% in February. And most of these repeats are loans are AA-C which I rarely invest in.