Serge,
Multisite has a lot of positive and negative aspects, i really like using the domain mapping for development.
But there is a better solution that has all the positives! Manage Wp WordPress Dashboard Check it out you get 5 free sites and it brings them all into one dashboard to manage… And its pretty cheap to upgrade imo
Chris,
I noticed a problem when i created a robots file for a site in a sub-durectory and then mapped it to its new domain. When i tried updating with the dashboard, i got the 404 that everyone is discussing. Once i reset the file from Network admin it worked!
Hope this helps
– Kagen