"I am sure I am not understanding something here, but what is the difference between the solution you are proposing and MU ? I have only 1 domain ... just a lot of blogs I am going to run on it, but your comment about less load is what I am curious about.
Thanks,
Jesse"
-WP creates less load than MU. Yes.
The difference in my link I referenced, is that similar to MU, it uses the same file structure for all blogs. That's where the comparison stops.
Essentially, it's 10 installs of WP, but only using 1 set of files that need to be maintained.
Each blog can have its own DB (or tables in a DB if that's how you want to set it up), each blog has its own users, and the whole 9 yards just like it was WP.
Well, it is WP, the only difference is one set of files as I mentioned.
Having one domain is OK too, with only slight modification to the stristr check for what domain is being called. you could look for blog1.domain.tld, vice domain.tld for example.
So, then you can add whatever subdomains you want, as you need them, or even run a mix of domains and subdomains.
If all your tables are in the same DB, you could work up some special queries, and address different tables to mimic some of the MU things (like recent posts from all blogs or something), or whatever.
It seems like the your main concern is load and, if that is truly the case, if I were in your position in terms of need, I would use my link referenced above.
Then again, since you have your own box already, depending on what you already have on it and what the specs are, MU should be just fine on it.
If you already have half your resources or more in use from other sites on it, then I'd opt (again, if it were me) for the option in the link as well.
Would MU still run? Yes. However, it might be a bit sluggish since it really prefers to be the only "kid on the block" for optimal performance.