The politicos' mutual stalking has reached unprecedented new levels this year: At least one side has started to spider the other's campaign website to track that campaign pages' precise word changes up to an hourly basis. John McCain's campaign published a side-by-side comparison of Barack Obama's Iraq War policy web pages on Tuesday using a new automated online tracking service called Versionista. The service, which launched two months ago, allows users to track and cache changes to specific web pages up to an hourly basis, depending on the level of filtering requested, says Peter Bray, its creator in Portland, Oregon....