Replace SBS2003 with SBS2011, want to keep the current profile on workstaions

I hope I could get some inputs on this -

We will replace a SBS2003 with SBS 2011 for a client. The server names, the domain names and the user account names are all the same.

If we leave the old domain and join to the new domain (again, same domain name and same user account), will the user keep the same profile? If not, how can we make it?

This is a clean install, not a migration.

Thanks

Jack