So, I don't have a lab to test this, hope someone else does or has done this exact thing. I'll try to be concise here.
Ex 5.5 Gal - Last Name, First Name Smith, John
Current Win2k3 Domain - First Initial Last name for login JSmith
Last Name, First Name for Display Smith, John
Q: As i migrate mailboxes to new E2K3 org, how will the GAL appear?
reason I ask is because standards were changed halfway through. The DN's for half the account are dn=jsmith etc, while the other half are dn=smith\, john etc. So inside ADUC, there's no consistency since it displays the account based on the DN format. I'm trying to decide if a cleanup to make all DN's last,first will adversely affect the users, or the GAL or make life easier in the long run, if i do it now before I connect the ADC.