I had that email as well and since I figured that the "new" CrewLounge PILOTLOG was more mature now, I made use of my grandfathering right. Let's see for how long this "lifetime subscription" will be valid...
And, yes, the transition from mccPILOTLOG to CrewLounge PILOTLOG was really easy and worked out nicely. Just follow the given instructions to the dot.