"Alice in Wonderland" rules the box office for the second week in a row. "Avatar" becomes one of the biggest grossing movies of all time.

3-D movies have become so popular that even 3-D TVs are going on sale soon.

But when studio execs say that 3-D movies are the wave of the future, I have to wonder: Is that a promise or a threat?

There is the gee-whiz element of seeing a film in (sort of) three dimensions, but there is a physical downside for some people.

If 3-D films literally give you a headache, it’s not just your overactive imagination. It’s the filmmaking process.

According to a wire story, "Doctors say those with less-than-perfect eyesight can suffer nausea, blurred vision and dizziness from 3-D movies."

The technology toys with depth perception, so if you don’t have clear vision in both eyes, you could get headaches and other side effects.

Apparently, 3-D flicks can have this kind of negative impact on 20 percent of the population.

Now, I personally don’t get ill when I watch 3-D flicks (well, except for the Jonas Brothers concert movie in 3-D, but that wasn’t the glasses making me sick -- thank you, ladies and germs!) But I feel 3-D victims’ pain. I get ridiculously nauseous watching movies with shaky hand-held cameras.

This potential sickness does, however, leave out a good chunk of the potential 3-D audience.

The good thing right now is that many theaters don’t have 3-D capabilities yet, so movies are released in both 3-D and 2-D formats. But, based on studios’ enthusiasm for 3-D, this could change rather quickly.

So is 3-D the great wave of the future? At this point, I hope not. At least so far, the 3-Dness doesn’t really add much. "Avatar" would have been just as effective and visually stunning in two dimensions. And it apparently was, according to people I know who saw the 2-D version.

The Jo-Bros’ concert film was no better by making fans’ waving arms seem three-dimensional. Then, fans got Joe Jonas throwing a pair of sunglasses at the camera so it felt as though they were flying right at viewers — spectacularly cheesy use of 3-D!

"Alice in Wonderland" is not particularly wonderful, and 3-D can’t change that.

As much as studios are pushing the idea of 3-D, the technology is not as impressive as they claim. There is still a sense of watching something decidedly fake. It feels not like real three dimensions but a very artificial facsimile, like those shiny 2-D pictures with figures that seem to morph as you move them around.

Granted, it’s better than Vincent Price in "House of Wax," but still ...

The other issue is that, right now, 3-D is still something that directors toy with (see my Jo-Bro reference above). It holds the danger of taking viewers out of the storyline so they can admire the technology. James Cameron controlled that fairly well in "Avatar," using the 3-D in more subtle ways that you might have expected. But that’s a rarity.

What do you think of 3-D movies?