I've spend the last week looking closely at Google organic referrals since Google Instant.
I've noticed an improvement in referrals for generic terms, and for company names, however, i've also noticed a slight decline in long tail phrases where a company name is part of the search term.
"company name" is up
"company green widget" is down
At only a week, it's hard to show patterns, so i'd have to give it much more time. In addition, I don't believe we'll know how much of that is from logged in search (Google Instant) or logged out search (no Google Instant).
How has your traffic faired?