Ah well...
This for example:
We have had a couple pbn sites get the boot from the index over the last few days, maybe penguin on the loose in our neighborhood?
The replacements we put up still get indexed right away, no problem there. Note: we only buy sites for our pbn's that are still in the index to ensure they are not banned, but new content gets indexed right away.
Also just bought a fresh new domain for another project, put up content, indexed and ranking same day, so I can't agree with the slow down thing.
The fact that you buy indexed domain with terrible history, anchors and backlinks, does not mean that it won't get penalized eventually.
Also, things work slower. I honestly think, at least from what I can see in the marketplace, that people here register crappy domains with horrible history, fairly abused in the past, yet not penalized. I haven't had single one of my clients complain about indexation issues or anything like that. Neither did I. It takes longer, but that's about it. I would really love to see some of those domains that you have trouble indexing.
No, it isn't wrong because Google only seems to do it when you pick up a domain and build a website on it totally unrelated to the topic/niche it used to be. Picking up a wedding domain with amazing metrics and building a real estate PBN is the type of thing I'm talking about and yes, I do believe Google is cracking down on that here. If they rip away the links they remove the authority, and without authority a PBN is slow to index. It makes perfect sense.
-ThopHayt
This also isn't entirely true. The effectivity of the domain, IF it retains the niche, will be higher as compared to a domain which is not relevant. Still, weaker niche relevant domain = stronger non niche relevant domain. Question is. Who decides what kind of niche the domain is? If I have a multiniche site, what niche is it? If I have site about weddings, photography and cookies, what niche is it? Is it defined by name? Defined by backlinks? Defined by prior content? If you use something completely unrelated, then yeh, the strength of your domain will be lower, but sure as hell not zero and sure as hell has nothing to do with indexing.
Also, your statement... No authority = not getting indexed. In that case, all those 0 backlink websites with premium names that registrars have been holding for years will not get indexed? And what about fresh domains? If I have a parenting niche money site, and I cannot find related domains backlinks wise, now what am I going to do? I can go with just non niche relevant or somewhat brandable. Does that mean I won't rank anything even with XYZ sites in my PBN? No.
There are so many many flaws in that statement mate. I respect you a lot, but I simply cannot agree with this.
Yeh and also, disclaimer, I am not writing this just to promote myself. 80% of domains are sell are niche relevant anyway, so not that it matters to me.
Well I've been tracking a few sites valued at mid/high 6 digits and they all are fed by PBNs and rank like motherfuckers.
So obviously Google will now go after these.
Especially PBN sellers using Gmail and Google Docs / Drive to deliver their reports, those will be the first to get the hammer.
Oh come on.

We are not in a Snowden movie. Honestly doubt they would risk so much by catching up with PBN networks. Not to mention, there are so much easier ways how to find PBN sites than dig through terabytes of shite in emails.