Just saw it for the first time! The Zeal category page for a local congregation's site that I did is showing up for a Google search for the keyword phrase. It's been a while since I checked so it may not be anything new, but it's the first time I've seen it.
Doing a search for allinurl:www.zeal.com/category/preview.jhtml shows about 105,000 results on google.com (110,000 on google.co.uk web search!). Looking at the pages, live and cache, it seems thats the end of the line if your looking at it from a PR respective. The child pages have session IDs or many query parameters and don't show in the cache.
I've found out last week that I have two sites in Zeal because I have seen the Zeal pages in Google. The pages that I've checked all show a PR of 5 which can hardly be a real PR. It appears that they have made it in the index due to Freshbot.
I have seen Zeal categories in Google for some time, so I don't think that is new. From this thread [webmasterworld.com], it seems that the category pages will not pass PR at all. All outbound links go through a redirect via a file named "exit.jhtml" -- and this file has been disallowed in Zeal's robots.txt file.