Google Analytics put out its first ever Benchmarking newsletter today, here are some highlights in case you did not receive it:

Site Metrics
Compared to a year ago, websites have seen reduced pages / visit, average time on site, as well as bounce rate.
Pages/Visit: last year 4.9, this year 4.5
Bounce Rate: last year 48.2%, this year 47.0%
Avg Time on Site: last year 5:49, this year 5:23

Traffic Sources
Direct: last year 36.5%, this year 36.8%
Referral: last year 21.0%, this year 19.4%
Search Engines: last year 27.0%, this year 28.0%
Other: last year 15.5%, this year 15.8%

Operating Systems
Windows: last year 89.9%, this year 84.8%
Macintosh: last year 4.5%, this year 5.2%
Linux: last year 0.6%, this year 0.7%
Other: last year 5%, this year 9.3%

Plus check out these attached graphics showing bounce rate distribution by country, plus average time on site distribution by country.