TechNet Wiki

The TechNet Wiki is a library of information about Microsoft technologies, written by the community for the community. Whether you write code, manage servers, keep mission-critical sites up and running, or just enjoy digging into details, we think you will be at home in the TechNet Wiki.

Here Articles Posted By one can be commented by others and also can be revised by others and Can see the History of Revisions of all the Articles. So every Article will be worked on betterment each time some one go through the article. Wiki articles are not personal blog posts, but shared community information articles.

More on this on http://social.technet.microsoft.com/wiki/contents/articles/695.wiki-about-technet-wiki-en-us.aspx

TechNet/MSDN Blogs

Technet & MSDN Blogs is Microsoft's blog site where many of its employees blog to a public audience. It has both individual blogs and product or feature-related blogs. The main page aggregates all posts in the various blogs.

The blogs accept comments and criticism from the public.

As per the Forum Comment in,

http://social.technet.microsoft.com/Forums/en-US/tnfeedback/thread/b15c0faa-60ea-4c9d-bef2-a155bb89e46d/

Non-MS folks cannot create a blog on the MSDN blog system, but guest posts are .

Conclusion

MSFT Employees can Create MSDN Blogs

Others Can write articles in Technet Wiki (Which can be revised and commented by anyone.)

Hope it helps for someone looking out for a difference.