I just discovered e-smith 4.1 this week and set it up on a box I'd set up - it's terrific so far! It does virtually everything a small business server should, and it's pretty easy to figure out. As long as we're wish-listing here, though, here's what I'd love to see in 4.2:
Easier mounting/editing of the default website/container. I'd like to be able to give certain users rights to it intuitively, and not have to connect as admin.
A mailing list manager - perhaps majordomo - with configuration through the e-smith administrator interface.
Checkbox-able support for ORBS and MAPS spam blocking in the mailer engine.
SSL-only access to the administrator interface. Redirection is nice (and if you have a NAT between the server and Internet, blocking the admin port can minimize potential damage from sniffing), but the password does travel in plaintext.
As it stands, it's a terrific package already, but these additions might broaden the appeal a little bit. I'll probably have my accountant get a copy for starters.
-Josh Turiel