David Drummond, Google SVP, Corporate Development and Chief Legal Officer has written about how they deal with government requests at googleblog. http://googleblog.blogspot.com/2010/04/greater-transparency-around-government.html There is now a tool to show information about those requests. Data is updated semiannually and there are some caveats.

tool: http://www.google.com/governmentrequests/
faq: http://www.google.com/governmentrequests/faq.html

other coverage:
The Washington Post http://www.washingtonpost.com/wp-dyn/content/article/2010/04/20/AR2010042002866.html
slashdot http://news.slashdot.org/story/10/04/20/197254/Google-Enumerates-Government-Requests?from=rss&utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+Slashdot%2Fslashdot+%28Slashdot%29&utm_content=Google+Feedfetcher

Philipp wrote: "Brazil leads the chart with 291 requests."
This is only the removal requests. Brazil also made 3663 data requests. Change the radio button setting on the tool to show this.

FAQ:
"Some requests seek the removal of multiple pieces of content, or seek data for more than one account. There may also be multiple requests that ask for the removal of the same piece of content, or data for the same account."

FAQ:
"Removal requests ask for removal of content from Google search results or from another Google product, including YouTube. For purposes of this report, data requests ask for information about Google user accounts or products."

FAQ:
"Some governments and government agencies choose to block specific services as a means of controlling access to content in their jurisdiction. The numbers we’ve reported do not include any data on service blockages. We are working on a separate tool to show you when Google services have been blocked by governments or government agencies."

The tool also has an overview page. http://www.google.com/governmentrequests/overview.html

Overview:
"The statistics here reflect the number of law enforcement agency requests for information we receive at Google and YouTube. They don’t indicate whether we complied with a request in any way."

Overview:
"You may have noticed that there’s a question mark for content removal requests from China. As noted in the map, Chinese officials consider censorship demands as state secrets, so we cannot disclose that information at this time. During the period that Google’s joint venture operated google.cn, its search results were subject to censorship pursuant to demands from government agencies responsible for Internet regulation. As we announced in March, users visiting google.cn are now being redirected to google.com.hk where we are offering uncensored search results."

The google blog also has an entry titled "Controversial content and free expression on the web: a refresher" http://googleblog.blogspot.com/2010/04/controversial-content-and-free.html

China censors strike Again
First google, now choogling
   New search engine specific to China, (www.choogling.com), launched to fill the void left by google’s departure, has now been blocked, and the site hacked!
   According to Mao Ze Wrong, one of the developers of the search engine, choogling has no plans to retreat to Hong Kong or move its operations outside of China. “Choogling was developed in and for China. We remain 100 percent committed to China and serving the Chinese netizens.”
   Choogling was launched in beta test mode early this month, but quickly attracted hundreds of millions of China-specific searches in China. The name was suggestive of a blend of China + googling = choogling. But choogling actually comes from “chu-ge,” (the sounds of a people surrounded by enemies) and “ling” (clever, as in response to a sharp insult).
   More details at: chinareallysucks.com/Site/New_Stuff/Entries/
2010/4/23_China_censors_say%3A_No_More_Choogling_.html

[unlinked]

> Choogling was launched in beta test mode early this month...

On April 1st, to be precise.

> launched to fill the void left by google’s departure

What void exactly? When you enter google.cn you can do searches for and in Chinese, similar to before, only that now you'll be forwarded to the hk domain first (which may be slower, but works from China most of the time).