Malcolm Coles pointed out a new feature in Google SERPs and posed some interesting questions last week. I don't think Google is treating "brand names" as site operator queries. Site operator queries only return results for a single site. Either way, both Malcolm's and Matt's examples appear to be navigational and/or what are referred to as "named entity queries."
Queries provide numerous signals that engines can use for insight about user intent. They are for the most part either informational, navigational or transactional (action) in intent but, some queries fall into more than one category. These queries are often classed as named entities. Problem is, it's difficult to surmise intent from a single query that may have multiple interpretations. Google already has related patents and recently purchased Metaweb, a company specializing in this field. One aspect that I haven't seen mentioned elsewhere in plain English, is that company names, product names, organization names, brand names and/or combinations thereof are named entities. Named entities are easy to extract online because they are often capitalized. If leveraged properly, they could provide a number of associative signals that are well worth considering.