Please see this similar thread on the Premiere cs5 forum:
When Adobe Premiere CS5 imports an Illustrator file it rasterizes it -- thus losing the advantages of the vector based workflow.
How does After Effects CS5 handle Illustrator files -- based on your experience.
I have a logo that scales over time from very small to fuill screen. The results do not look that good in Premiere -- lots of aliasing and pixilating when I scale the large image to the small size -- so I am thinking of doing it in AE and then using it in my Premiere project.
Your comments appreciated!
Thanks for both the search results link and the search link itself.
I found this link especially answered my question --