Well in this case, the link was a 65 Mb video clip, which was also posted to Slashdot. If anyone does something which is saturating the whole 100 mbps uplinks to two separate switches (servicing probably 25-30 machines including some centralized services like customer mail machines), not to mention racking up bandwidth bills that most customers can't afford to pay (even if we were to give them a reduced rate), then yes, we'll probably take some sort of action. Unfortunately, we have to place the stability of our machines and network above the needs of one site... We're working on some other things to help with this (such as placing limits (generous limits, but still limits) on individual machines. Generally, we deal pretty well with slashdotting, but the size of the file in this case caused a problem.
I realize the announcement could have been phrased more carefully... we're not out to get anyone, but (especially with shared hosting), we have to look at the big picture. As our TOS states, we reserve the right to take corrective actions we deem necessary in the case of resource usage we consider excessive.
In any event, we didn't permanently shut down the site or anything... we did write the user in question and they linked to the file offsite (and also put up a bit torrent version).
A few notes if you think you're going to get seriously slashdotted.
1) Give us a heads-up in advance if you think you're going to be getting hit really hard.
2) Try to link to a static site, or rebuild dynamic content and then cache it - images are OK, but database driven stuff is much more likely to cause resource consumption issues or unavailability.
3) Obviously try to keep image sizes small etc. You might also want to put images on a separate subdomain.
4) Don't post a link to a 65 Mb file to slashdot. :>
Hope this clarifies things a bit.