Google Base URLs competing with organic listings?

Will a Google Base URL compete with an equivalent organic URL for indexing?

[monkeylytics]

Does anybody know if Google uses Google Base URLs as a source of URLs to crawl?

We're planning on uploading a test Google Base feed. I have to put in some tracking parameters in the URL to measure the effectiveness of the feed. However, it would make life more complicated if Google crawled the the tracking URLs, indexed them, and since they have the same destination pages as our normal URLs, I might have issues like duplicate content, canonical URL issues, I'm now receiving data from basic SERPs as well as more Base specific pages (although the distinction here is blurring anyway but still...), etc.

Or do the backends of Google Base and Google Web search exist independently of each other (even if the results of the former might show up in the results of the latter?)