cites for blockquotes

[Mike Shaver]

markdown at fredcondo.org wrote:
> This is definitely something I would use, but, as the philosophy is to
> have text markup that's rather similar to email, how about this
> syntax:
> 
>>This is really very pithy, and will be widely
>>circulated.--http://www.penny-arcade.com

Mmm, yes, the doubledash is more emaily, to be sure.  I think I do want 
the citation on a separate line, though, both because I think it would 
be less ambiguous to the parser and because that's how I generally cite 
things in that style:

     This is really very...you get the idea.
         -- Gabe

An alternative would be to borrow from the email quoting pattern of many 
  mailers, and use:

http://www.penny-arcade.com:
> This is really very pithy, and will be widely
> circulated.

Mike