I use both Google and Baidu Search. For Chinese content Baidu cannot be matched, but search results are not as accurate as Google. I just cannot find what I need as quickly and sometimes not at all with Baidu. For English content Google is tops in anything. Baidu is specifically for the Chinese market and content, and no other.
Currently Baidu's mapping data in China is so much better than Google, but then again there are government security issues that make mapping in China problematic. I can track a friend through China using Google Maps when he is on VPN, but his GPS location does not correlated with his actual physical location on Google Maps. But the Google Maps lack the depth of detail of Baidu, such as landmarks, stores, schools, buildings, shopping centers, often parks, virtually everything. Google's sat maps in China are almost all off. Baidu's Streetview is pretty great, but then again there are security issues that sometimes block the actual location image. Baidu does not update their Streetview as often as Google in Canada. Google has no Streetview in China. I therefore use a combination of Google and Baidu for mapping and GPS work.
Searching Chinese content in Chinese on Google is currently pretty bad. Yes, there are results but the depth is just not there. I find that English-Chinese translation and vice versa is about the same with both search engines. I use Google's translate much more, but it is not very accurate.
Google kills Baidu in any English search, hands down. Technical, news, whatever, Baidu in English is terrible.
The world of information and internet is distinctly split between China and everything else. I span both worlds and therefore currently need both search engines. I welcome Google if and when they hit China and will then rigorously test both search engines. Google has a huge amount of work to be done if they hope to even dent the native Chinese market, but I see hope. Chinese netizens are looking for alternatives to Baidu, just for a different perspective. The opportunity is there for the 750M people in China who are online.