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Hi Steven, It's very hard to find definitive info about this update since, to my understanding, Google is yet to even confirm that it happened but from what I can gather, it was another revision of onsite quality. Search Engine Land has about the most helpful article I've managed to find on it yet. To save you some legwork, one of Search Engine Land's previous posts on the topic (linked to in the one above) also provides a link to two Google resources on this topic. Note that they're old links more related to Panda but it does talk about what Google views as "quality" which is what this Phantom update is focussed on. More guidance on building high-quality sites Search Console Help: Create Valuable Content There's a bit of reading there but hopefully it's helpful.

Keyword research will be key, and that's really going to be where you want to focus down. Find related terms, long tail, and opportunities you may not have considered in the past. Don't get too held up on the head terms to start - Optimize for long tails (with head terms in them), then once those get traction you'll see progress on the head term. You really need a process/strategy around keyword research. It's not as simple as going to Keyword Planner and picking a few; competitive analysis and proper research is key to the whole process. When I talked about page depth, there is only so many clicks a user will take on a site before they move on. Basically what I meant is to organize the architecture of the site (navigation) so that the user needs as few clicks as possible to reach the products. Fewer clicks (hops) for the user also means fewer hops for Googlebot. Fewer hops between products means more quality pages indexed, more quality pages indexed means a wider spread of keywords to be found on, more keyword rankings = more traffic. Optimize for the customer first, since that's how you make money. Make the site easy to navigate, and you'll see a lot of benefit from that.

Very good question. It is ultimately a matter for yourself. I always take the primary keyword head on - even if there is no realistic chance of ranking for it in the short term.  However I also make sure that I target keywords off the same branch that I can rank for.  I usually start with 5-7. I believe you should always have your eye on the ultimate prize. Ubersuggest is good I also like Semrush.com - as you also get to see what organic keywords your competitors are getting traffic from.  Semrush may further fine tune the keywords you target. On a nexus between primary and secondary - if you are targeting "dell computers" and words around that frame - once you get some traction with your other keywords then you may start to rank for "dell computers" but at 300 etc. . In fairness though it is impossible for anyone to suggest a true nexus as it will all depend on your seo optimization and the keywords you initially target and what you actually publish/do. Hope that assists and good luck.

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