Funny, Shrek doesn't look like Spider-Man...

The green ogre, however, did a very good webslinger imitation in putting up $121.6 million debut for Shrek the Third.

The CGI sequel posted the third-biggest opening weekend of all time, and the biggest animated opening of all time, per stats from box-office tracker Exhibitor Relations.

Shrek the Third also set a new standard for Shrek movies, easily topping the $42.3 million put up by the original Shrek in 2001, and even surpassing the monumental $108 million taken in by Shrek 2 in 2004.

Why, if Spider-Man 3 hadn't opened with $151.1 million just three weekends ago, Shrek the Third would be the hottest thing around.

As it is, it's the second movie this month to bow with at least $100 million (after Spider-Man 3, natch); the third such movie likely will hit later this week, when Pirates of the Caribbean: At World's End sets sail.

According to Exhibitor Relations' Jeff Bock, the box office has never seen three $100 million-plus openers in the same summer, much less the same month.

"This is the biggest summer on record—this will be the biggest summer on record," Bock said Sunday.

The new Harry Potter (opening July 13) and Transformers (opening July 4) also have good shots at joining the nine-figure opening-weekend club, Bock said.

By the time the summer is over, Bock has predicted a record-breaking $4.5 billion in combined ticket sales.

Oddly, one guy who wasn't bullish on the summer, at least publicly, was Shrek's DreamWorks boss Jeffrey Katzenberg, who told reporters at Cannes that the studio hoped for "a very, very good weekend [for Shrek the Third], but I don't expect us to set any records."

"I think they were trying to downplay it," Bock said. "You had to expect this would open bigger than the second [Shrek]. I think the marketplace was ripe for this type of opening."

If it makes Katzenberg feel any better, Box Office Mojo's Brandon Gray remained skeptical that Shrek the Third will outdo Shrek 2 in the long run. The latter is the third-biggest movie of all time, thanks to a monstrous $441.2 million gross.

Already, Gray pointed out, Spider-Man 3, with an overall take of $282.4 million has fallen behind its 2002 franchise originator, which had $288.6 million after three weekends, and 2004's Spider-Man 2, which was at $302.3 million.

Thanks to Shrek the Third, Spider-Man 3 fell to second place ($29 million) after two weeks on top of the box-office standings. It could drop another place next weekend when Pirates moves in—not that Gray thinks the hero, or the ogre, is doomed.

"These are huge franchises, and these are sequels people want to see. That's why we're getting these $100 million openings. It's not a calendar quirk." Gray said. "Clearly, there is room in the market for all three."

There does not, however, appear to be room for movies that are not named Spider-Man, Shrek or Pirates of the Caribbean.

Georgia Rule (fourth place, $3.74 million; $12.9 million overall) looked cooked in only its second weekend; 28 Weeks Later (third place, $5.5 million; $18.9 million overall) continued to lag behind its zombie predecessor, 28 Days Later.

The thriller Disturbia (fifth place, $3.73 million; $71.4 million overall) hung in there—again, down only 21 percent in its sixth weekend.

The next stop for Nicolas Cage's Next ($1.1 million) was a step out of the top 10. In four weekends, it has "grossed" $16.5 million.

In limited release, Luke Wilson's The Wendell Baker Story, costarring Owen Wilson and cowritten by Andrew Wilson, made $48,120 for a per-Wilson average of $16,040. (Its per-screen average was a less impressive $2,831.)

The period drama Brooklyn Rules—if the mid-1980s can be considered a period—pulled in $58,886 at eight locations, giving costar Alec Baldwin a box-office victory over ex-wife Kim Basinger's Even Money, which only made $22,465 at six theaters.

The weekend's biggest little movie was the music-fueled Irish love story Once, which scored $61,901 on just two screens, meaning its per-theater average of $30,951, bests even Shrek's, which averaged $29,507 at 4,122 sites.

Here's a rundown of the top 10 films based on final Friday-Sunday tallies compiled by Exhibitor Relations:

1. Shrek the Third, $121.6 million
2. Spider-Man 3, $29 million
3. 28 Weeks Later, $5.5 million
4. Georgia Rule, $3.75 million
5. Disturbia, $3.73 million
6. Fracture, $2.3 million
7. Delta Farce, $1.9 million
8. The Invisible, $1.3 million
9. Hot Fuzz, $1.29 million
10. Blades of Glory, $1.1 million

(Originally published May 20, 2007 at 3:26 p.m. PT.)