Yeah I don't know - they removed RescueTime and some others. It seems pretty incomplete to have some but not others. I don't know what criteria they're using to decide which should be listed.
Not every company is notable, and certainly not companies at the two-guys-and-no-revenue stage (compare to your local dry cleaner, who is probably actually profitable).
This list would provide a better understanding of YC. Given that there is no SEO juice with links from Wikipedia and given that being on the list resulted in 2-10 vists per day for RescueTime (when we were on it), I see lots of benefit (in term of being accurate/complete), no harm, and no real significant benefit to the companies lists.
If the information is public I don't see any good reason why it must be a subset.
I would think that either you'd include a list that is as complete as possible, or not include it at all. Doing a partial list because you don't WANT it complete is just warped.