By Joshua Rich
Updated March 27, 2009 at 04:22 AM EDT

Okay, time to put on your 3-D glasses, box office fans! This weekend sees the debut of Monsters vs. Aliens, DreamWorks Animation’s initial foray into what it promises will soon be the norm: movies in 3-D. In honor of this landmark event, I tried to write this column in three dimensions, but only got so far as “DreamWo…” before I started to feel totally car sick.

So I’ll spare you the barf and just say that, of course, Monsters vs. Aliens will win the weekend opposite two other big new releases — The Haunting in Connecticut and 12 Rounds — and you can read on to see exactly how much I think each movie will make.

1. Monsters vs. Aliens — $66 million
Recent spreads in Entertainment Weekly and several of its sister Time Inc. publications make it clear that the marketing might behind this animated family film has been in overdrive for quite a while. So there’s no doubt that its premiere will be big. But how much will the film earn? Well, considering that families are probably desperate to see a big-screen extravaganza right now (Coraline and Race to Witch Mountain have fared well, but both are fading), it could draw an unusually high number of ticket buyers. Add in the fact that many of the tickets to the film’s 1,550 3-D showings (it’s in 4,104 theaters total) will cost more than the usual multiplex admission, and we’re looking at a debut gross in the range of Ice Age 2‘s $68 mil, which arrived on this weekend three years ago.

2. Knowing — $12 million
Nicolas Cage’s sci-fi flick sorta surprised last weekend, with a $24.6 mil win. But it should drop an expected 50 percent or so against such stiff competition this time around.

3. I Love You, Man — $12 million
That $17.8 mil bow was a tad weak, let’s be honest, but I’d like to believe that Paul Rudd’s R-rated buddy comedy will hold onto its audience better than any other sophomore movie this weekend, because it’s the only major funny film in the marketplace. And, um, because it rocks! (Sure, I’m biased.)

4. The Haunting in Connecticut — $12 million
The trailer, poster, title — everything leading up to the release of this allegedly fact-based horror-thriller starring Virginia Madsen has baffled folks around these parts for being so kind of banal. To that end, I expect a perfectly pedestrian $12 mil opening weekend gross, which is about average for movies of this ilk.

5. 12 Rounds — $8 million
The plot of this action movie from WWE and wrestler John Cena sounds like an odd mashup of Taken, Die Hard With a Vengeance, and, I guess, The Wrestler. But if that doesn’t sell it to you, try this: It’s directed by long-under-the-radar action auteur Renny Harlin! Seriously, I’m actually thinking of going to see it now.

Now, how do you see the weekend playing out?