Domains that don't begin www

is this still an issue?

[Dabrowski]

ok, I've never really done SEO before, but as a self proclaimed web developer it's about time I did.

So, I'm starting by redesigning a site.

I've split the site into home and business users, for the benefit of both. I was going to use an initial 'header' site so the structure would be:

www.mydomain.co.uk
corp.mydomain.co.uk
home.mydomain.co.uk

Is there any SEO implications with this, or should I go for:
www.mydomain.co.uk
www.mydomain.co.uk/corp
www.mydomain.co.uk/home

Would appreciate the advice, I can read up on the page structure etc but need this to get started.

[edited by: caveman at 6:23 pm (utc) on Dec. 23, 2008]
[edit reason] Removed specifics, per TOS [/edit]

[phranque]

is there relevance among the three areas?
are all three of those domains really going to have enough critical mass to stand alone?

if both answers are "yes" or "no", there is room for discussion.
otherwise, the answer should be obvious.

[Dabrowski]

Yes, and yes.

The corporate and home sites will be big. The corp site around 70 pages are currently on my sitemap, and home not so big but at least 20. On top of this there will be an ever growing FAQ on each.

The split is really for the convenience of my clients, home users don't want to see business services and vice versa.

The header site will be the smallest, just a few pages describing my company and services in each business sector, with links to the relevant sections of the split sites.