As was mentioned earlier, there is no way most of these nano and pico operations can last for long (no offense to anyone here that is running one of those). UNless you have a brew pub, I'm not sure how you can subsist on anything smaller than a 10 bbl system. I am filling 30 bbl tanks now and the amount of money I am making off a 30 bbl batch is not enough to make me or any of my partners rich by any means. I'm making about 1/3rd the salary I was when I left my job and working 2Xs as much. Granted, we are forced to go through a distributor which takes a nice, hefty cut and while we are permitted to have a tap room we can not sell growlers or other packages on premiss.
So in that case, I think there will be a bust eventually as many of the nanos and picos fail or simply get bored and quit. OTOH it's so easy to start a nano or pico now that I believe they will continue to pop up as other ones fail.
I'm sure there are exceptions across the nation but the picos and nanos operating locally are simply terrible. Most of these folks are people who got the idea to open a brewery before they learned how to brew or some of them obviously learned to brew and their friends and family told them how great their beer was and that they should open a brewery. What's amazing to me is, in some instances here in the south some of the latter are actually thriving because craft beer is so new here a lot of people think "that's just the way it is supposed to taste". But as people tastes evolve I think even these places will begin to fail.
FWIW I think there is money to be made in the brewery world and I think you can definitely support yourself and make a good living but it takes a lot of money and time and effort to get there and you have to be selling a lot of beer or have a very busy tap room or successful restaurant driven brew pub to get there.
Now everyone's situation is different but how long are you willing to keep making 1/3 less money and working 2x more? At some point I think a lot of people are going to throw in the towel because there is no light at the end of the tunnel.