With GoDaddy, I notice that the amount of backorders a domain receives affects the "tries" GoDaddy uses to catch the domain. I assume GoDaddy tries harder for domains with more backorders so the domain enters auction & GoDaddy makes more from the backorder. In my experience in catching pagerank domains, when I used multiple GoDaddy accounts to backorder the same domain, that yielded a decent amount of tries & higher catch rate per domain. GoDaddy won't be able to beat snapnames on a high quality name, but I have seen GoDaddy on very rare occasions beat out Snapnames - probably because the domain only had one (my) backorder @ Snapnames. I assume all backorder services (GoDaddy, Snapnames, etc) all focus their strengths most on the domains with the most backorders.
I also wanted to clarify that domains backordered at BlueRazor are caught using all of GoDaddy's registrars. Eg, a domain backordered at BlueRazor can be caught by GoDaddy itself, go china domains, go australia domains, etc.. The domain ends up in your bluerazor account. The issue comes - that if a domain is backordered via BlueRazor & GoDaddy, the domain is automatically awarded to the GoDaddy bidder(s) & the bluerazor backorder fails.