Beepster
I will point out though that the "pinky/little" finger is rarely used or even really recognized in more traditional techniques. That's not to say it is a useless appendage BUT simply because it is so much shorter and unweildly I would not focus as much on your pinky (it doesn't even merit a letter name in the PIMA system).
Developing it is laudible but unlike the fretting pinky is not nearly as critical and may even hinder progress.
Just my thoughts on the matter. YMMV.
Cheers and keep at 'er.
Full disclosure, I've only been finger picking for a couple years now. It was a technique I ignored for 30 years.
I would say it depends on what you're trying to achieve and what you're trying to play or create. If you're goal is to learn traditional techniques, learn your favorite radio songs and such, it's probably not an important appendage.
But if you're trying to maximize your options, which for me was important reason to learn finger picking in the first place, then it needs to be developed with the rest of your fingers. Also, personal experience only here, it minimizes hand movement and cleans up sloppy playing.
For instance, I've got a song I'm working on in 130 BPM, with three beats per beat...err, per thingy...something like that. Basically a triplet pattern per beat, and that's a pretty fast pattern for me and has taken months to get up to speed, staying in tempo and playing clean. It is a 12 note pattern that is kind of Travis picking in the first half dancing between the low E and the A, D, G then finishing off with a B-E-B-G on the bottom strings - and that requires good pinky and ring finger management there, otherwise you're dropping your hand down to get to the B-E-B-G pattern and then lifting back up to do the Travis E-A, E-D, E-G pattern, over and over again.
For me, that will create a sloppy result. So, I think it just depends on what you want to do with this technique. I find that hand movement creates slop, and that keeping it in place while the fingers work makes it tighter and cleaner. That requires strong pinky control to do interesting patterns that involve the high E string, as far as I can tell.