Writing my own blog system

Hi, this looks like a useful site, so I was wondering if anybody could help me.

One of my clients has an ecommerce site and a separate blog on Wordpress.

The blog is a fairly basic affair, but what it lacks in style it more than makes up for in terms of useful content.

However, we have developed our own blogging system which is integrated with the CMS of the ecommerce site.

What I want to do is move all the content to the new blogging system, and leave stubs redirecting people to keep the old links active.

Originally I was going to copy the data but from what I've read here and elsewhere that is a complete nono.

Anyway, thats the scenario. Currently the blog gets a lot of hits, and I know that Google likes blogs, so my main question is this: how will Google know that the new blog system is a blog?

Does that make sense? The existing blog is part of Wordpress. Google knows Wordpress is a blog site so treats it accordingly. Is there anything I can do to my new blog to let Google know that it is a blog?

I hope that makes sense. In an ideal world there will be a metatag like "content = blog" but I think I will have to work a bit harder than that...