Hey Egreg, I've met Peter Shankman and love what he's done with HARO. However we're doing a few things differently.
First, it's global from day one. So we have a much lower volume of overall queries to start with. However we've already made connections in the UK, India, US, & Dubai (where we're based).
Second, opportunities are public and shared. This is a huge no no with HARO look at this link for example: http://www.publiseek.com/opportunity/seeking-new-stories-for...
Third: any content creator (not just reporters) can use it. That includes movie producers (product placements), event organizers (speaking opportunities), etc.
Also we're putting a bit more focus on design/branding. Hope this answers your question. Do you use HARO?