Update Fritz was the beginning of the transition from a monthly update to an incremental index. It caused a lot of comments, because plenty of people were happy with an index that only changed once a month. But since this was not quite good enough for evaluating pages once in a month an update was done a summer when there is low search engine traffic due to seasonality ,this update called everflux is expected to have a certain amount of change to the index every day or so. Note: sites shouldn't use "&id=" as a parameter if they want maximal Googlebot crawlage . If many sites use "&id=" with session IDs then Googlebot usually avoids urls with that parameter so check up with your site session id and remove usage in that fashion for maximum crawlage
