As far as I'm concerned, this is a handheld with TV out, and the only thing that's "hybrid" about it is that it's combining both of Nintendo's business lines.
I'd personally call that a consolidation, but I imagine Nintendo likes the hybrid messaging more since it sounds a lot better than "We dumped our console line."
I think its status as a true hybrid is entirely dependent on what differences there are when played as a handheld and played on a TV.
If the device only supports one resolution and clock speed for its hardware and simply uprezes or uses the as is resolution of the handheld when played on TV, then it is most definitely just a handheld with TV out.
But if they actually have two separate CPU/GPU profiles for the system, downclocked when used as a handheld to maximize performance there and then another profile for full power to provide a true HD experience when played on TV then I would, personally at least, consider that to be a true hybrid of a console and handheld device.