About five years ago, it was the subject of a CCTV documentary which criticized its
sales practices in China. It argued that Baidu ad buyers were locked into a cycle: if they refused to renew their ad buys, they would disappear from Baidu search. Partly as a result of this, Baidu has worked to improve its search and sales practices.
Outside of China, the parts I use the most are 百度百科_全球最大中文百科全书, which is Baidu's version of Wikipedia. My only complaint against that it is too commercial and that too many ads appear there, but I am sure that Kaiser Kuo can give the order to remove all ads immediately, which would please me immensely.
The other part of Baidu I use a lot is 百度预测-大数据 知天下 which is the Chinese version of Google Trends, and tells me what is trending up or down in China.
These are the two parts of Baidu I use the most.
As for other services, now I find myself using Weixin/Wechat more and more, since that is where the trendy people tend to go.