I am utterly mystified by Safari's popularity. I'm still waiting for them to release a version that has a feature set as useful as IE already had 6 years ago.
<soapbox>
Let's look at the plusses & minuses, with appropriate sarcasm interjected:
Safari's advantages:
1.) Safari has tabbed browsing - although I call this a "gee whiz" feature, as it's prettier than opening a page in a new window but doesn't add any real functionality beyond that. (Unless you count the ability to suddenly close 10 open pages at once, instead of just one, if you accidentally hit the close box.)
2.) Safari has built-in popup blocking
3.) Safari handles CSS "correctly" (I put that in quotes because as a 7-year user of Explorer, I have yet to see an IE CSS bug substantially interfere with my browsing or page design. If you follow the link given above <http://www.macedition.com/cb/ie5macbugs/> for a list of IE5 bugs, the first thing you'll see on the page is that IE has "very good" support for CSS1 and "good partial support" for CSS2... and specifically says, "Stop! Are you experiencing unexpected behaviour in IE5.x/Mac and being tempted to blame it on bugs? Don't be too quick to blame the browser" because many of the things that people think are bugs in IE are design errors on the page.)

Safari's disadvantages:
1.) "Web archives" (in the beta) are a JOKE - you can't include linked pages in an archive, just the single page you are looking at, and it doesn't even preserve the URL of the page! IE lets you DL linked pages up to 5 links deep, AND displays their original URL when you open the archive.
2.) Safari's "Downloads" window is a joke. Download history limited to only your 20 most recent downloads? No way to find out your download speeds without getting out a calculator? No way to find out the original URL you downloaded a file from? No ability to re-download a file once it's already been downloaded, other than by going back to the original download link that safari won't tell you the URL of? (Guess if you corrupt or lose a downloaded file, you'd better have the original URL written down somewhere.) The 20-DL limit and the dearth of information are just plain inexcusable. I frequently rely on these functions in IE's Download Manager.
3.) You can't download a file to a specific location by dragging the link to a Finder window. You need to go into preferences and manually change the download folder every time you want to download a particular file to a different folder. This is so inconvenient to me that it offsets the small "gee whiz" factor of the tabbed browsing. Who at Apple thought that when I drag a link to a downloadable file onto my desktop, I was more likely to want to save the file's URL than to download the file? Must've been the same genius who thought up the perfectly round mouse.
The above two complains alone - the Download Window's egregious deficiencies and being unable to start a download to any folder by dragging a link- are by themselves enough to make Safari so impractical that I can't even consider it a finished program.
4.) If you copy an image using ctrl-click and selecting "Copy image", and then try to paste the image into an rtf document or an email in Eudora, it pastes the URL of the image instead of the image itself. WTF? Why can't there be a "Copy URL of image" menu selection, and have "Copy image" mean the same thing the Copy command means in every single other Macintosh program?
5.) After tabbing to a pop-up menu form field, you cannot jump to a selection in that menu by typing its first few letters, like you can in IE... you must repeated ly down-arrow to get to your choice (big fun in one of those "What country are you form?" menus that have 150 choices.) In fact, it seemed to me that sometimes, doing this actually will instananeously jump your window to select a part of the page containing those letters. (Can't get it to happen now, though...)
6.) The tabbed interface is prettier than opening separate windows for new pages, but this very minor plus is offset by the fact that it makes it too easy to accidentally close and lose 10 pages at once... if you accidentally hit the close box for one reason or another, it doesn't warn you before closing and completely forgetting about whatever pages you had open in the other tabs. (Yes, there are third-party software or applescripts to recreate the set of tabs you had open. But that is both inconvenient and a cop-out.)
7.) Constant, repetitive "Safari could not connect to the server" messages for sites that other browsers have no problem loading, which take several reload attempts then suddenly open as if there was never a problem. What's up with that?

Don't get me wrong: I really try to avoid Micro$oft's products whenever possible. But in this instance their product simply has a superior feature set, and fewer drawbacks, than any other browser I've tried. I think Safari has a LOT of potiential, and will eventually be a much better and more usable browser than IE currently is... once it's finished.

I'm not saying any of this to be contentious or put anybody down - if Safari works for you, I have no complaint about you using it, I'm just honestly mystified as to why anyone chooses it in light of all the drawbacks and missing functionality.

End of sermon.
</soapbox>
Mike