A lot of people want to be able to run as many sites as they want with just one installation of WordPress. Before WordPress version 3.0, you had to use WordPress MU (Multi User) which was not in line with the actual WordPress codes. So basically you would be able to have any number of sites running on WordPress MU but you may miss out on some functionalities. This was not such a big deal for many people who liked the idea of running many websites/blogs from just 1 installation but now with the release of WordPress 3.0, this has been made even more simple.
The greatest benefit of being able to have a many sites on one single wordpress installation is maintenance. You just need to update your files in one place rather than update it in several places as soon as a new version comes out. It is advisable to upgrade to the latest stable version of WordPress as soon as it’s made available. So this is a big time saver in terms of updating but as well as launching new sites.
When I first tried WordPress MU, I was very keen to get my sites running but I eventually found out that to be able to run different domains on WordPress MU, you need to get a wildcard mapping for subdomains. Now because WordPress MU has been merged into WordPress 3.0, you have the same problem. I remember how difficult it was to set up and I eventually gave up.
So if you have your main blog at www.example.com and want www.myotherdomain.com to be hosted on WordPress 3.0, then you’ll have to do a wildcard mapping. Now if you’ve got a dedicated server, you can get it done quite easily but if you’re on shared hosting, then this may be a problem because some hosting companies don’t allow wildcard mapping. If you manage to do it though, there will be another problem. If you had a subdomain like subdomain.example.com, it will stop working because of the wildcard now. So you’ll have to come up with a way to handle that.
I think the idea of hosting multiple sites/blogs is very appealing especially if you want to create niche websites with just a couple of pages. However WordPress 3.0 is not ideal for that purpose nor is WordPress MU. On the other hand WP Hive which is a plugin for WordPress works brillantly.
When I heard that WordPress 3.0 allows multisite creation, the first thought that came to mind was that WP Hive will become dead (redundant) now but that’s not the case. The official documentation of WordPress 3.0 shows that you need wildcard mapping whereas with WP Hive, you only need to add the domain you want have have wordpress on as an addon domain.
I like simplicity above everything else. For those on shared hosting, I suggest you have a look at WP Hive if having multisites/multiblogs on 1 wordpress installation is what you need.