How soon will inward links appear?

What factors contribute to the time it takes for Google to recognize links?

[drhoden]

Does it make sense that NONE of our known inward links appear when using Google's [link:<url>] tool? We have had links in place for well over a month, including a Yahoo listing.

What factors come into play? Can site design thwart our efforts? All of the inward links point to the root level of our domain (no fancy stuff). Can the landing page affect the visibility of our inward links?

To what extent do major directory sites (Yahoo) contribute to the inward links of a site (according to Google)?

Other data: Viewing access logs, we know that the pointing sites have been crawled by Google, MSN and others.