Unfortunately, when I went to try it out at MSN the request timed out. I imagine this is related to the spotty latency problems I've been experiencing all day and does not reflect on MSN.

This tool will be quite helpful in understanding the relationship between sites and will further the ability for folks that don't have their own crawlers to better identify sites that exhibit "hub" or "authority" linking behavior (PDF).

It probably won't replace the benefit of crawling specific sites and networks of interest (especially those with which MSN has poor coverage), but that takes time and resources that aren't always available.

Added: The MSDN blog has a really good graphic to explain the difference between linkdomain and linkfromdomain if you don't grok the difference. :)