XP3 is still in "automatic updates"

OK, so I procrastinated the install of sp3. Coincidentally I read about the
deadline of patches and things on July 13,2010.
So I read a post or two about where one can read and go update on the web
xp3. I glanced at a few of the support pages, when I remembered that Its
probably already download and have had it 'sitting' ready to install for a
while; in my automatic updates. I am relieved due to the size of this
update.

So, can I assume that Windows did download this and all I have to do is
click install and no further action or investigating on my part is
necessary? Can you please let me know if there is something I need to be
aware of before I install this?
Thanks in advance....
my specs now: Windows xp home edition sp2