tedster - 6:48 pm on Nov 21, 2010 (gmt 0)
You are seeing that. If ComScore were counting all the 3-second pauses as explicit search, Google's numbers would have zoomed up dramatically, rather than inched up.
ComScore explains their methodology in detail here: Google Instant Search Reporting [blog.comscore.com]. Three second pauses are considered IMPLICIT core search, and not explicit core search. Explicit search requires an explicit user action, not a pause.
User actions that qualify an explicit query include those where a user hits "enter," clicks on an algorithmic or sponsored result, clicks one of the various refinement links (such as past 24 hours, etc.) or clicks on a vertical search tab to execute the query in a different channel (such as News or Image Search).
Any query with such explicit action is counted in Explicit Core Search. Query result pages without explicit user action, but with a pause of at least 3 seconds, are considered as indicating ‘implicit’ engagement and will count towards Total Core Search.