The LG V line has always been the best phone in the LG line-up in my opinion, the LG V20 was superb. It was also the more niche product, with some quirky features, in particular the first 2 models used dual displays and had removable batteries.
When LG updated the V30 to the v30S ThinQ it received quite a bit of criticism, it was basically the same phone with some added AI and minor improved specification at a very high price. They then later updated this device again to the LG v35 ThinkQ giving it a Qualcomm Snapdragon 845 processor which was again priced very high.
New reports suggest LG maybe implementing 5 cameras on the new LG V40 ThinQ giving you three on the back and 2 up front. It is completely overkill but it appears to be a logical progression, we already have triple rear cameras, so why not have dual front.
At least one of the dual front cameras will be used for a face-unlock function, it seems this could be a stereo configuration allowing a 3D map of the face to be recorded.
The rear cameras are believed to include a standard wide lens, LG's signature ultrawide lens, and a third sensor for an as-yet undetermined purpose. This could be a zoom lens, or it could be dedicated to bokeh or depth of field effects.
It has been said that the design will be quite similar to the G7 but scaled up, you will get a notch, but this is removable in a similar manner to the G7.
Most of the internal specification will be similar to any other high end phone of 2018, using a Qualcomm Snapdragon 845. Thankfully LG should be keeping the excellent Quad DAC.
With the LG v35 ThinkQ only being announced recently, and using a Snapdragon 845, it seems a little excessive to be released the V40 this year, as each device will cannibalize each other.