I have encountered this problem in both the most recent Mac App Store release and the newest beta. When Exporting documents to PDF for print, rasterization always occurs on seemingly random vector objects. Grouped objects are also usually rasterized. I noticed that the files I am having this issue with are ALWAYS set as the PHOTO document type, regardless of what option I select. If I create a new document with a PRINT or PRINT (Press-Ready) document type, paste all the objects/layers into the new document, and export immediately to PDF, I can get a clean export (though grouped vectors will still sometimes rasterize). After exporting, the document type will immediately switch back to PHOTO, so if I want to export again, I have to create another new document, paste my content in, and re-export. I don't know if there is an item in some of these documents that is forcing a switch in the document type or if there is some other issue, but it seems completely random. The first time I encountered the issue, I was exporting a design with a photo and I thought this might be the problem. However, I have since created 100% vector documents and have had the exact same issue. For smaller documents, my workaround, though tedious, works. For larger documents, it's just not practical.