WhatLCD allows users to quickly detect the model and type of LCD monitor connected to their system. It is basically a one-click system query that uses the results into a Google search. The application is designed for those who need to look up monitor information whether for compatibility issues or for searching appropriate drives.
I have tested this application with a dual monitor system: external LCD in addition to the MacBook integrated monitor. However, WhatLCD only managed to detect the type and model of the MacBook monitor alone. Information related to plugged-in displays is actually not that hard to find; you can either access the Hardware section in the About This Mac tool or run the Display application from the System Preferences panel, both of them actually show the correct number of displays.
Considering that the results are not entirely accurate and the fact that it does not effectively offer needed functionality, WhatLCD becomes a bit redundant for most Mac users. The application is certainly very simple to use but not entirely convenient so you may want to skip this until future releases.