Hmmm, I haven't yet found them at Apple's Downloads, but the updates are posted here (Lion) and here (Snow Leopard). Looks like the real McCoy.
Your linked MacUpdate page (Snow Leopard) is headed "Update 8," but every doc linked to on the page is headed "Update 7."
On the other hand, the SHA1 check sum posted on that page, which differs from the Update 7 checksum, agrees with the checksum of the d/l I got by clicking on the "Download Now" link, which, I guess, means...something.
I went with Software Update with no ill effects.
Edit: As I was posting, the 1st and 3rd links changed to Version 8, but the 2nd link is still at Version 7.