Adding hard drive to a laptop

[cga2000 <cga2000@optonline.net>]

I have decided it is ample time to add disk space to my old laptop and
came up with the following plan:

1. Buy a large HD with caddy and stick it in the "mega bay" where a
   useless 100M Omega zip drive currently lives.
2. Lavishly partition the new drive & create the usual file systems.
3. Copy my current partitions to their new drive namesakes.
4. Swap the drives.
5. Reboot.

In a perfect world I will be up and running with my current systems and
the luxury of a spare hard drive ..  right?

Is there a catch?

Thanks,
cga