For a couple days now my Software Update has been telling me that I should update Safari to version 6.
(Apparently it has a number of features, such as pop-up blocker, which allow it to catch up to Firefox.)
However, nowhere does it appear or can it be found on Apple's Support - Downloads site. (I prefer to download it separately rather than have Software Update do it.)
What's up with that?

Pardon? I have only used Safari and, for a long time, it has had a "Block Pop-up Windows" feature. Given your experiences, expressed in the "Blocking pop-up windows" thread, it would seem that it's FireFox that needs to catch up.

I'm not sure why you continuously slam Safari but I think you can now relax as I'm sure everyone has heard the dissing sufficient times that they all "get it".

Sorry, I misremembered what the details were. They are as follows (and it was the "Do Not Track" feature that I meant):

Safari contains new features, including:
Smart Search Field. Safari now has one field for typing both searches and web addresses.
Offline Reading List. Safari saves entire webpages in your Reading List so you can catch up on your reading even when you don’t have an internet connection.
Do Not Track. Safari can send the websites you visit a request not to track you online.
Password pane. Manage your saved website logins with the new Password pane.
Baidu. The leading Chinese search engine Baidu is now a built-in option for Chinese users.

But thanks for the kind words. I'll take the recommendation under advisement.

I don't know whether this is one of them, but there have been instances in which updates, Airport Utility comes to mind, were not made available other than via Software Update; it's always annoyed me, but it's been pretty infrequent up to now (although I can envision it becoming all-encompassing, or, should I say, all-enclouding).

Well said!

The ad hominem remarks qua attacks are tiresome and to my sensibility outweigh the usefulness of the forums.
Enjoy my absence.

The trouble with the "Block Pop-up Windows" feature (which, as you say, Safari has had for a long time), is that it doesn't always work. It still allows JavaScript to create a new window in response to a user click on something on the page. In effect, all it blocks is windows that are "popped up" by JavaScript that runs as part of the page load (before there's anything to click on) or in response to timers.

Case in point. There is a website that I used to visit frequently to view comics. I had "Block Popup Windows" enabled, but going to the site only shows the first comic I've subscribed to. To see the next, I would have to click on what is in effect a "next comic" button. That click gave the site permission to open a new window, almost always as a "pop-under", despite my preference.

I found that disabling JavaScript before going there worked wonders. I eventually stopped going there altogether, which works even better.

I notice that Safari 6.0 no longer has the option. Apparently it's always on now. I just checked in at that site, and didn't get any pop-unders this visit. (But then, I didn't always. They were clever enough to only occasionally give you one.)

I wasn't sure whether you were talking about the option to disable/enable javascript or block popup windows but in Safari 6 you will find both options in Safari > Preferences > Security.

Safari 6.0 stand alone/downloadable is available here

FWIW: I know not of this site, ergo I caution a bit of caution. The site may indeed be dandy, it's just that I dunno.

Since I still can't find a Safari 6 download on Apple's website I'll offer up an emphatic "STAY AWAY!"

(For what it's worth, I can't find any Safari d/l for OS X later than 5.0.6 [for Leopard] on Apple's website.)