On Monday night, CSI: Miami scored 22 million viewers, effectively grounding time-slot rival LAX in its second week on the air. NBC's airport drama pulled in only 8 million pairs of eyeballs, ranking Heather Locklear and Co. a distant third in the Nielsens. (Ouch!) Meanwhile, Shannen Doherty's much-anticipated debut on North Shore did nothing to help Fox's struggling nighttime sudser, which was trounced by WB's 7th Heaven, for goodness sake. Seriously, if Heather can't save her show, what hope does Shannen have?