The ComingSoon.net Box Office Report has been updated with studio estimates for the weekend. Be sure to check back on Monday for final figures based on actual box office. After setting a new MLK Jr. weekend record, the J.J. Abrams-produced monster movie Cloverfield (Paramount) was clobbered by two new entries, and while the spoof comedy Meet the Spartans (20th Century Fox) and Sylvester Stallone’s return as Rambo (Lionsgate) were running pretty close on Friday, the Spartans remained ahead over the weekend, grossing an estimated $18.7 million in 2,605 theaters compared to Rambo‘s $18.1 million. Ironically, neither movie was screened for critics until opening day proving the studio theory that reviews rarely help movies like these. The Diane Lane serial killer thriller Untraceable (Sony/Screen Gems) also did relatively well, bringing in $11.2 million in 2,368 theaters as it opened in fifth place.