cites for blockquotes

[Mike Shaver]

John Gruber wrote:
> I've got to tell you -- should have mentioned it before, really --
> that I take syntax changes super seriously. I always sleep on
> anything new. It's my hope that Markdown makes it for the long haul,
> and so I want to do everything I can to avoid any "Geez, I wish I we
> hadn't made that mistake back at 1.0" decisions.

Oh, certainly.  I didn't mean to cause the impression of a rush!

I'm going to leave that patch running on my MT install and see what my 
users think of it (there are some picky HCI types there, so I'm sure 
they'll find _something_ to complain about), and I posted it here mainly 
so that others could also experiment.  If you can make use of the code, 
that's also great. =)

Mike