Thought it might be useful to start putting together a list of Bing (very basic) optimisation priorities.  Hopefully this will turn into a more detailed analysis of the differences between G and B, just going to see what evolves out of it according to people's priorities. Here's what I've noticed so far:

1.  Bing and Yahoo rankings vary significantly, bing is clearly operating on a new set of criteria from Yahoo but Bing results seem to be closer to Google than Yahoo is/was

2.  Exact phrases early in the page Title seem to be much more important than on Y or G 

3.  Bing allows more than one page from a site to rank in the top ten without it being indented (does Bing even indent?  Haven't seen any yet)

4.  IBLs don't seem to matter as much to Bing (?), there's still a focus on on-page factors like with MSN

5.  (Tentatively) going to suggest that domain age is more important to Bing

6.  Bing ranks video the same way Google does, unlike Yahoo

7.  Keyword phrase in domain name more important for Bing?

Just a few observations to kick start this.

My initial impresison is that where Google tries to establish an general feel for the relevance of a page in their index to the search phrase, Bing is still putting a lot of emphasis on on-page factors and exact match.  Having said that it's results are closer to Google than Yahoo so it's clearly sharing some ranking signals.

I'm along with you both, bing, or msn has always seemed to be more about the on page optimisation rather than off page. Im just waiting for the day microsoft decides to do some conflicting rankings to google so we have to optimise one way not the other, but fortunatly so far its seems to be fine to optimise for both in a similar manner.

No mate, its getting more unpopular by the day: http://www.alexa.com/siteinfo/http%3A%2F%2Fwww.bing.com. To be honest, I think your time would be better spent creating a youtube profile and some videos for a website than worrying about bing: http://www.alexa.com/topsites/countries/GB - youtube has a far bigger reach.

Bing and Yahoo are quite a mistery for me. I have websites ranking in Google and Bing but no where in Yahoo and vicecersa. Though I noticed that if it ranks in Google, it ranks even better in Bing.