blog.domain.xxx or domain.xxx/blog?
 

What do you prefer?
blog.domain.xxx or domain.xxx/blog ?

Do searchengines treat both ways the same?

I'd go with a sub-folder.
Having it as a subdomain, it's just "more work" to rank it.
Google treats it as a "new" domain in the end of the day.

New folder vote too. /BLOG

Yes, Google treats subdomains more as new domains.

As others said a subdomain is just another site, a director it's a part of a site! You decide what is better for your project!

One more vote for /blog.

i like /poo

If blog is going to be on WordPress you may want to go with the subdomain and use a different ssh/ftp username as well.
You could also redirect domain.xxx/blog to blog.domain.xxx

I used to do both at the same time with PBNs :upsidedow

All depends on what you're doing.

depending if you want the blog for the domain, or, make the blog a new domain, i.e...

myofficialpornblog.domain.xxx

personally, we´ve always used subfolder for blogs, /blog :2 cents: