It seems that this might change in due time, as Microsoft apparently has already updated the “Where's My Phone Update” list, and in there it previously mentioned “Except Samsung Omnia 7 models” – only to have it changed to the more favorable “Except Samsung Omnia 7 models, which are Testing at this time.”
One step at a time, after all, you can't expect the Omnia 7 to run before it is able to walk. For the moment, we're all too happy to take baby steps instead, and wait for a possible end-of-October release date for the Mango firmware update on an official basis. Be patient, Omnia 7 owners – after all, since you've waited for so long already, what is a few more weeks or even months of tapping your fingers on the table?
