It was time to get new servers, and migrating services from old servers at Netscape to new ones at meer.net instead of migrating the machines themselves means less downtime (because we don't have to turn the machines off and physically carry them over) and less risk (because we can make sure everything works on the new system before we turn it off on the old one).
Netscape/AOL donated both the old servers and the new ones to the Mozilla Foundation, however, so they will be moved from Netscape/AOL to Mozilla Foundation space shortly now that services have been moved off of them.