What does it take to get top serps in MSN?

I have a site that , unfortunately one of the biggest general jobboards in the country as competition with literally hundreds (thousands?) of subdomains to gain indexing on MSN. In fact they are one of the biggest sites on the internet period.

They're seperate subdomain for each slight variation of key term which is filling the top twenty to forty slots for these.

Do any of the others engines give preference to subdomains -- Which?

I'm weighing subdomains as an alternative.