(This was an email to a friend, and then I realised it was worth tidying a little and posting. I gave up on the 'tidying' part, because my hands are cold.)
On linking to other sites and stuff, shuld one do it? Yes, if it's valuable/helps the reader, but my (acquisitive and greedy? XD ) policy is to try and link to other places that benefit me - e.g. Squidoo, within blogs. Which also means I can vouch for the quality at the other end. Can't always do this, of course, but very often you can recreate a similar resource to link to - such as a new Squidoo lens. The more you write, you'll realise that you'll be referring to the same awards, topics or genres or author or something else, so it makes sense to create an overview/index page about it. These may end up being more valuable than the original posts and lenses, in their way, either for the navigational aspect, or because people really really want a nice guide to that topic.
Basically:
1. Don't let people leave unless it's via an Amazon or other link that you WANT them to go to.
2. Make people want to return, so if another link adds value, it cancels out the above. So (good, reliable and useful) links means that people will come back to see what you post, even though they leave to visit each link. And that improves their opinion of the site itself.
3. Google does look at what you link to and who links to you, but if you're following the above rules it should even out (basically, on topic and quality. Links from other good sites means your site is obviously good. Roughly. So links from lenses and stuff = good).
4. When considering whether to write about something yourself instead of linking, consider:
a) can you add something, bring something of your own to it? (if yes = awesome new content, if not = are you just regurgitating existing content? If so, is it worth it for the internal navigation/organisation benefit (e.g. a list of books by an author with links to your reviews) and when expecting no other traffic other than within your blog/portfolio)?)
b) And of course, is it on topic? If it's not then it will probably be a bit too random. Might work very well on a separate site or a Squidoo lens though (you could write it and decide where to stick it later).
So in summary, don't link out, write new stuff instead, unless it is to a better resource that people will want to visit that you cannot recreate and improve without simply copying which is pointless unless it helps you organise your site better AND is very relevant and on-topic.