At this point, the BotD feature (as announced) is being rolled back, as it did not prove to be very popular. The Ratings are restored to the previous scheme, which it turns out was simpler and did not require members to make decisions regarding BotD, etc. Members just rate a blog based on its own merits.
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However, the concept of BotD is being retained (and may be expanded further). So, for instance, any blog or reply which received the most Ratings the previous day will be the BotD, and so forth.
Thanks.