I've got a 10 year old reference site, 500K visitors plus month 18% direct, it receives 68% from SEs, 59% from google A 3 year old sweepstakes sit that gets about 38k visitors 12% direct to site and receives 72% from SEs, 35% yahoo, 21% Google
80% of my traffic is from SEs. Really I think the percentage is higher because a good proportion of the remainder is repeat visits from people who first found my sites via Google.