Some of these are known quantities. Some are things Google shouldn't answer.
1. If Google tells us what they're doing about paid link networks, paid link networks will route around that. I bet Google loves it when paid link providers spend $10K/day on AdWords and Google instantly catches and devalues their links.
3. Yes, time-based relevancy exists. Google has lots of ways to filter this (for example, if something is "newsy," and gets lots of links from "newsy" sources, they'll put it on page one temporarily and then drop it once the news cycle ends--this also affects Suggest).
5. This is a common concern, but I've never heard of it happening.
6. Google Local. They're taking reviews into account and building their own review system.
7. Yes, click-throughs affect rankings. If the #2 ranking gets as many clicks as the #1 ranking, it'll probably be bumped up. This signal is stronger for brands (for example, if a search for "hacker news" brought up a newspaper's topic page on "hackers" ahead of news.yc, but most searchers were looking for news.yc, Google would alter the rankings.
In my experience, for #1, Google claims to penalize paid links, yet when I look at (my) major competitors, they all utilize paid link networks. Didn't take very much investigation on my part to find it, either -- just ran a backlink checker and checked out some of the pages. The ad networks all advertise themselves in their link networks.
Although I don't do a lot of SEO work, it's disappointing when it feels like I can't do techniques that other places are doing. It's not a time issue, either -- many of these paid link networks have been on my competitors systems for a decade.
What google says they do is often very different than what they actually do.
1. If Google tells us what they're doing about paid link networks, paid link networks will route around that. I bet Google loves it when paid link providers spend $10K/day on AdWords and Google instantly catches and devalues their links.
3. Yes, time-based relevancy exists. Google has lots of ways to filter this (for example, if something is "newsy," and gets lots of links from "newsy" sources, they'll put it on page one temporarily and then drop it once the news cycle ends--this also affects Suggest).
5. This is a common concern, but I've never heard of it happening.
6. Google Local. They're taking reviews into account and building their own review system.
7. Yes, click-throughs affect rankings. If the #2 ranking gets as many clicks as the #1 ranking, it'll probably be bumped up. This signal is stronger for brands (for example, if a search for "hacker news" brought up a newspaper's topic page on "hackers" ahead of news.yc, but most searchers were looking for news.yc, Google would alter the rankings.