[blauwbilgorgel]

> If I think of a a lot of things my users would search for and try to create valuable information for them concerning those queries... is that great content or are those doorway pages?

  Create a useful, information-rich site, and write pages 
  that clearly and accurately describe your content.
  
  Think about the words users would type to find your pages,
  and make sure that your site actually includes those words
  within it.

  Doorway pages are typically large sets of poor-quality 
  pages where each page is optimized for a specific keyword
  or phrase.

  Some examples of doorways include:

  Having multiple domain names targeted at specific regions
  or cities that funnel users to one page
 
  Templated pages made solely for affiliate linking
  
  Multiple pages on your site with similar content designed
  to rank for specific queries like city or state names

>If when someone writes a nice article with a link to my site I give them a a few months of my service for free... is that good customer service or a link scheme?

  Avoid tricks intended to improve search engine rankings. 
  A good rule of thumb is whether you'd feel comfortable
  explaining what you've done to a website that competes
  with you, or to a Google employee. Another useful test is
  to ask, "Does this help my users? Would I do this if
  search engines didn't exist?"

  Any links intended to manipulate PageRank or a site's 
  ranking in Google search results may be considered part of
  a link scheme and a violation of Google’s Webmaster
  Guidelines. This includes any behavior that manipulates
  links to your site or outgoing links from your site.

  Large-scale article marketing or guest posting campaigns 
  with keyword-rich anchor text links can negatively impact 
  a site's ranking in search results.

  The best way to get other sites to create high-quality, 
  relevant links to yours is to create unique, relevant
  content that can naturally gain popularity in the Internet
  community. 

  Effectively promoting your new content will lead to 
  faster discovery by those who are interested in the same 
  subject. Avoid: attempting to promote each new, small 
  piece of content you create; go for big, interesting 
  items. Avoid: involving your site in schemes where your 
  content is artificially promoted to the top of these 
  services. Avoid: spamming link requests out to all sites
  related to your topic area. Avoid: purchasing links from 
  another site with the aim of getting PageRank instead of
  traffic.

> If I create a press release on PR Web and link to my service with an appropriate keyword ... is that participating in a link scheme?

  Links with optimized anchor text in articles or press 
  releases distributed on other sites can negatively impact
  a site's ranking in search results.

  Note: I wouldn't expect links from press release web 
  sites to benefit your rankings, however.

[mtrimpe]

What's your point here? That you find these guidelines so specific that they don't leave any room for interpretation?

[Crito]

I think the point here is that this is only a complicated topic if you are trying to follow the letter but not the spirit of the guidelines.

So you can't figure out exactly how you can game the system... boo hoo.