If you are planning on transferring your domain name to a new registrar, be aware that you cannot make any modifications while the domain name is in process of transfer.
For example, let's say you made a request to transfer a domain name yesterday and the Admin Contact confirmed/approved the transfer. The domain name is then placed in a "Transfer Pending" state while waiting for registry approval. Then, let's say today you need to update the nameservers so the domain name points to a new server. You will find the updates and changes you make will not be saved or applied to the domain. Initially, it may look like the changes are saved but if you log out and back into the registrar the domain settings will be back to the original settings.
So, my recommendation is to make any updates, changes, and modifications to domain names before you submit a transfer request to move to a new registrar. Just be careful not to modify the Primary Account Owner information before making a transfer request... as this will then require a 60 day wait (before a transfer can occur) if you change this.
More domain philosophy soon! Ron