Great question — answering as the UphillTech team:
I read the question as Larry did. If available, fetch a RSS feed (or use a service's API ) with e.g. PHP via a cron job . I use this technique to (among other things) fetch the number of likes from Facebook.
Full answer by Ivar: https://webmasters.stackexchange.com/a/49036 (CC BY-SA 3.0).
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