If you are interested in excluding Google Instant Preview from NetInsight there are a couple options.
If you currently have data in your profile from Google Instant Preview and would like to not have this data included in your reports you can simple add a filter (User Agent Breakdown) that 'does not contain' "Google Web Preview" (sans double quotes).
If you would like to exclude this data from ever being processed this can simply be done by going into your profile and adding the following rule:
Options -> Filters -> Excluded User Agents:
Add -> Exclude User Agents 'that contain' Google Web Preview
Another option would be to exclude this from the primary data but include the results in your Robot & Spider reports. To do this add the following rule:
Options -> Marketing -> Robots/Spiders:
Add -> Name of spider: Google Web Preview -> Continue
Locate the new 'Google Web Preview' entry (likely bottom of the list) -> Visitors -> Add -> Group 'user agent' 'that contain' Google Web Preview
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