Which blog system

[birdz]

We're planning or creating a multi-user blog system (somewhere around 10,000) and I have narrowed my choices down to b2Evolution and Serendipity. Has anyone used one or both of these systems. We want something that is easy to install and customize.

Neither of the blogs have all the custom options that we want, so we need to be able to easily edit the code and database.

or if you know of another blog system that would be better, let me know. I did a little research of all the blog systems on this site.
http://asymptomatic.net/blogbreakdown.htm

thanks for any advice

[WebWatch]

Looking at your list, I don't see any of the Blog hosting softwares.
Is that intentional ?

I would recommend you to look at these two:
Blog System

and

BlogHoster

Both these 2 are hosting systems, allowing you to set up your own blog hosting site. Not sure if that was your intention. Just thought I'd mention them.