No. Calling it Mer would be factual. Shouting aloud MeeGo is smart marketing. They're riding on the goodwill that N9 generated. And on the disappointment that it wasn't continued.

If they would just say they're bringing a Mer based product on the market, there would be excitement in TMO and some smallish geek circles. Now there's much larger pool of interested people.

Of course, most people who recognize MeeGo from N9 think about the innovative UI, and Jolla will have different UI. So in that kind of sense it has a chance to backfire if the UI is a disappointment.

But on the whole I think it's a smart move to shout MeeGo for the time being. The time to educate about Mer is later IMO. It's good to remember that N9 itself wasn't really MeeGo but Maemo with MeeGo compatibility. In fact, looks like Jolla is more an offspring of MeeGo than Harmattan IMO.