10.2. Inbound Links
You want as many inbound links as possible, provided these links are not from link farms or link exchanges. With this caveat about inbound linking from "naughty neighborhoods" understood, you cannot have too many inbound links. The more popular (and the higher the ranking) of the sites providing the inbound links to your site, the better.
Inbound links are considered a shorthand way of determining the value of your web site, because other sites have decided your site has content worth linking to. An inbound link from a site that is itself highly valued is worth more than an inbound link from a low-value site, for obvious reasons.