According to some details on the FCC tests performed on the Nokia Lumia 1520, there will be two versions. One with and one without built in Wireless Charging.
I’m a big fan of the convenience of wireless charging. Just setting things down on a charging plate, fatboy pillow, charging stand, car holder etc without plugging it in…bliss.
Difference between RM-938 and RM-940 is that DTM feature and WCDM1700/2100 (Band 4) will be disabled from RM-940, and RM-940 will GPRS support multi-slot class 10. In the testing reported here multi-slot class 12 has been available as worst case in all the samples. Additionally, difference between RM-940 and RM-938 is that RM-940 has only Wireless Charging interface pins in the backcover, while RM-938 has built-in Wireless Charging (WPC/Qi) loop. This HW difference was tested according to FCC KDB 648474 D03 Wireless Chargers Battery Cover V01R02
Wireless charging built in may mean a slightly thicker device – or perhaps just slightly more expensive if, due to the large 6″ display of the 1520 there’s more internal space for wireless charging.