I asked Mstar directly if they are still on UTOPIA and got the following response from Henry Rodriguez, Customer Service Manager:
The change to the UTOPIA website must be an administrative oversight, as Mstar continues to be the largest and most experienced service provider on the UTOPIA network. Any questions about UTOPIA’s website should be sent directly to the UTOPIA staff.
Forum commenter DIE-HARD has reported that he is an Mstar customer and hasn’t experienced any change in service or received any kind of notification of changes. I also put in an inquiry to one of my contacts at UTOPIA, but I haven’t heard anything back yet.
UPDATE: I’ve heard back from UTOPIA who said it is a temporary measure. They’ve started selling in Tremonton as has been rumored on the forum and wanted to make sure that Mstar would be prepared for a large influx of new customers before they’re listed.