Thanks for the review, MD! To be fair, Baidu wasn't up-to-date until the end. You noticed how small the installer is, so it is expected that the bulk of the offline database will have to be downloaded the first time it is used. That blue Update text is the command to manually update, by the way.
Baidu Antivirus is targeting Brazilian users (maybe also other nations, I'm not sure, but I do know they're targeting Brazil) and you will find many Brazilians angrily complaining in their forum that they don't know how Baidu got installed in their machines. Of course, most of these people have actually found the Baidu forum, but not the Control Panel where they can easily remove it. Of course, those people were tricked by bundled installers (last one I saw Baidu hidden in was ImgBurn's -- downloaded from the official website, by the way -- one of those setups where you have to choose an "Advanced Installation" mode and then you still have to uncheck the product or products that are being "offered", bundled with whatever it is you really wanted). Naturally, we all know to recognize this type of tactics as typical of Potentially Unwanted Applications. In this case, it's (probably) a second antivirus in your system when you clearly didn't ask for one, which we know can cause instability, slower performance and other problems. So instead of paying for ads in download sites and such, no, Baidu is actually paying for PUP tactics to deliver their product. I guess they just really want everybody safe... right?