Move2Moo is a new service which has partnered with Lambda Solutions to provide course content migration services to institutions and companies adopting/migrating to Moodle from another LMS. They currently offer a demo site where you can also test a conversion of a single course (right now Blackboard Vista/CE, WebCT are supported). The service is paid, though no pricing is listed on their site. If you’ve a large (or small) institutions making the switch and you fit the criteria, this might be a great way to save some time and effort.
Unfortunately I do not have a WebCT/BB Vista backup file to test out with their converter, but if anyone does and can please post your experience in the comments.
Other services (data retention, bulk course creation) are also available. Contact them today for more information: http://www.move2moo.com/Contacts.aspx