2 Blogs?

i am planning to set up a website with a blog which is written by two individuals. i would like to use only one blog, for administrative reasons.

i was thinking about having two separate categories with links to each one from the non-blog homepage. but then, i guess there is no way to have customized interfaces for each section, e.g. a different picture as heading for each writer.

can u advise me on a good solution?