this last update when checking last Wed. for 10.5.8 was only 165 mgs. I checked on the Apple update page and it showed two hundred and something mgs. Well, tonight I downloaded a video from Vimeo.com and along with it it downloaded MacOs update 10.5.8. O.K. no problem. So I tried closing safari and it asked do you really want to quit the download. Huh? I thought if it was a true update download it wouldn't matter if safari was running or not. Is something going on here??