Ask HN: Parsing Access Logs for Amazon S3

My startup is looking at building an metric service on top of some static resources we serve from Amazon S3. We started investigating this and came across the following statement on log delivery:

==Start Documentation== Amazon S3 Documentation: Best Effort Server Log Delivery

The server access logging feature is designed for best effort. You can expect that most requests against a bucket that is properly configured for logging will result in a delivered log record, and that most log records will be delivered within a few hours of the time that they were recorded.

However, the server logging feature is offered on a best-effort basis. The completeness and timeliness of server logging is not guaranteed. The log record for a particular request might be delivered long after the request was actually processed, or it might not be delivered at all. The purpose of server logs is to give the bucket owner an idea of the nature of traffic against his or her bucket. It is not meant to be a complete accounting of all requests. ==End Documentation==

I'm looking around for any information I can find about the reliability of the logging service. I've seen some reports of logs taking several hours to show up. Have others had experience building similar systems or with S3 logging who can share some insight?

(Full disclosure, link to my unanswered Stack Overflow question: http://stackoverflow.com/q/4923756/223440)