No, you are right - I just have a lot of other stuff on my Touch. For example, we download our lectures in my program as videos, so that takes up a bunch of memory. After each semester, I then disable those lectures from syncing to my Touch, but still keep them in iTunes.
I also have a lot of music, but if you don't, then there is no need to worry. (Our other main iPod is an 80G classic, so I was spoiled with being able to always keep everything accessible.) I guess in the big scheme of things, an 8G iPhone should be enough for school apps - if you don't expect your usage to change. I am not sure what the cost difference is, but I would probably go with the 16G to keep your options open. Besides, you want room to add some fun time-wasting games, too!
Also, one last thing, please make sure you research if you decide to buy any subscriptions and/or bundles. I remember reading that one set only gave you a year, so when your time was up you no longer had access to anything unless you renewed.
Poof. With another, however, have you access to update within the year, but whatever you had downloaded up to that point stayed with your phone without having to repurchase.
When I started seeing that, I decided to wait a little longer until I could get confirmation of which programs to buy.
Please let me know how the nursing apps are if you do decide to purchase some. I would LOVE to have a Nsg Dx reference available on my Touch.