I can see how people get confused with this forum being called Vegas - Video and then there being one called Vegas Movie Studio. Prehaps this one should be renamed Vegas Pro or Vegas Pro - Video.
Vegas Pro 1.0 was audio only, so that would fall under the Vegas Audio forum.
Vegas Pro 8.0 is the current version, and it's very normal and accepted for a forum to cater to the current version. The "studio" version went through several names, yet no one complains that it's forum matches the current version.