I just REALLY REALLY want videocenter back. I was using it to download my podcasts for my commute to work.
Right now I'm just using the built-in RSS reader and downloading them that way. It works, but it's a pain to manage.
I tried gpodder but it requires libglade and I heard that glade apps won't be working with OS2008.

The only apps that I really miss right now are:
Video Center
VNC viewer (I used this a LOT with work)

I will be great when they finally get ported!