Until Transmit has a more robust built-in "favorites" system (we're working on it for 2.0!), here's a temporary savior: the Favorites Editor.
This mini-application allows you to do one of two things:
• Import Fetch bookmarks
• Edit your favorites
The interface is simple and easy to use, so not a whole lot of description is necessary: simply double-click the icon and you're presented with the editing tab. Here you can edit your existing Transmit Favorites. Switch to the Fetch Import tab and you can import all your old Fetch bookmarks in one simple step.
This tool is a temporary stop-gap and, as such, is unsupported. While we have encountered no problems with it during testing, we encourage you to use it at your own risk.