Elton John was briefly hospitalized yesterday morning with a "serious respiratory infection."  Apparently, he started feeling sick during a show last Sunday night.  His doctors gave him some antibiotics, and recommended that he rest for the next seven days.  He had four shows scheduled in Las Vegas this weekend, so those had to be canceled.  He says,  "It feels strange that to be able to [do] these 'Million Dollar Piano' concerts . . . I love performing the show and I'll be thrilled when we return in October to complete the 11 concerts.  All I can say to the fans is 'sorry I can't be with you.'"  Elton is scheduled to begin a European tour next Friday.  For now, it sounds like that's supposed to go on as planned.  Elton is 65 years old.