Since shortly after vista's release most competent consultants have
advised waiting for at least SP1.
And, I assume, you define "most competent" as those who agree with
that position.
You see statements like this, all the time, and with every new version
of Windows that comes out. My view is that it's a nonsensical
statement.
Hotfixes to Vista (and every other version of Windows) come out all
the time, as needed. At some point Microsoft decides to roll up all
the existing hotfixes into something called a service pack (they may
or may not add other hotfixes at that time). But there's nothing magic
about the day when they decide to do it, and it's entirely at their
discretion as to when to do so. Because it's an arbitrary decision as
to when to release it, it doesn't really represent any significant
milestone in the life of the product.
If you don't want to install a new version of Windows immediately,
that's certainly your prerogative. But it makes just as much sense to
say "wait six months" or "wait 197.8 days" as it does to say "wait for
SP1."
Personally, my experience with Vista is that it's been very stable,
and by and large I like it a lot. I'm not sure that everyone needs to
rush out to upgrade to it, but for anyone buying a new computer and
wondering what operating system to put on it, I certainly recommend
Vista.