Need opinion on Blog on subdomain and blog on subdirectory

Hello

Is it good to have the Wordpress blog on a subdomain or on a sub directory Please let me know the pros and cons.

Say I hv a blog at http://blog.domain.com and and it has PR 4.
If I manage to redirect all the links from that to http://domain.com/blog, how is it going to affect my PR.

I want the subdirectory blog because hv to create different blog for different section where I can not accomodate category as It has some lmitation.

Please advice me.

 

This is a very interesting dilemma and here goes my .02

If you setup different blogs on different subdomains (and preferably, each one on a different IP address), you should be able to gain at least some milage in terms of SEO, as each subdomain can potentially be treated as an independent website by the robots and spiders in general. With judicious cross-linkage across the primary domain and the subdomains, reasonable link popularity benefits could also be derived.

On the flip side,
a) you'll need to obtain independed backlinks pointing to each subdomain to improve the chances of gaining the benefits mentioned above and
b) Your primary domain will be at somewhat of a disadvantage (also in terms of SEO) as the total page count of your main site (one of the factors affecting rankings) will get split across the root domain + all the subdomains.

All in all, I'd say this is a tough choice and the ultimate decision should be made only on a case-by-case basis.

HTH