Not going to happen.
I know. I mean, we will never going to see TNG in HD anyways. I mean, they would have to redo all the special effects again, since it was edited on video! NOT GOING TO HAPPEN, YOU F*CKING GEEK IDI*T! NOT! GOING! TO! HAPPEN!
Neva eva TNG in HD. Move along! Nothing to see here! Muharrharr!
There is a GIGANTIC difference between what they have to do to get the episodes into HD and what they'd have to do to get the episodes into "3D."
To make a proper 3D movie there needs to be two cameras right next to one another recording the action. One for the left eye, one for the right eye. Various techniques are then used to transmit the camera's information to the appropriate eye to create a 3D effect.
TNG was not filmed with this technique, like all TV shows and most movies it was filmed with a single camera for the shot. (Obviously most cameras at once for different angles of a shot, but not a 3D camera set-up.)
So how are non-filmed-in-3D movies released in 3D? (Like Titanic and many movies that came out following Avatar.) By essentially faking it. You load the film into a computer, cut out various elements and "layer" them in a shot and with filters and other techniques this creates a 3D-like effect through the 3D glasses. But there's a problem.
IT'S NOT TRULY 3D! Because there's no way of knowing what information the other eye is supposed to have! You're essentially playing with Colorforms on someone's glasses. And even when a LOT of time and money is spent doing this (as was the case with a small handfull of recent 3D releases) the results aren't great, nor are they true 3D.
People said TNG wouldn't be made in HD because we realized the level of work that have to go into it, but CBS/Paramount proved us wrong and are doing it and, surprise, it's taking a LOT of work to do it and there's been mistakes and quality issues along the way. Even problems when it comes to recovering footage.
Converting a 2D picture into a 3D one is not, by any means, an easy or cheap one. And when it's done it doesn't have the greatest of results. To do it best takes a LOT of time and money, which if we use this BD project as a guide is something they're slightly stingy with on even redoing effects with perfection.
There'd also be no benefit to making the show 3D since there's no way to give a true 3D view since the show wasn't FILMED in 3D!