B.M.
N.,
What a great friend you are. I felt so alone when our preemie was born, friends never knew what to do. You can get them gift certificates to food places (dinner was so hard to do with being at the hospital all day). Even though this is a scary time, it is also a celebratory time. We got several "with sympathy" or "I am sorry" cards and notes, these were actually quite painful, because in our eyes there was nothing to be sorry for. Even though things were touch and go, we were happy to have a baby and happy that he was alive. So, anything you can do to share in that joy I am sure would be appreciated.
Preemie sized clothes (nothing with zippers, only snaps) are nice (most babies r us stores have a little preemie section). While the babies won't be able to wear clothes for a while, its nice to have them, so when they are ready, they have stuff already there.
For your work care package, things to keep them busy at the hospital...books, magazines, sudoku, etc. They may not be able to hold the babies right away, so this will give them something to do while they are sitting in the NICU.
Really, any sincerity will be appreciated. If/when they show you pictures, be sure to tell them (even though the tubes and wires may be there) how beautiful the babies are. When you have a preemie, you get robbed of a lot of the normal celebratory things because people don't know what to do or say.
Best of Luck to your friends.
B.