Yes, that's exactly how they're named. The new Samsung Galaxy handsets have undergone a name revamp though design wise they're still same old.
The Galaxy W features a 3.7-inch WVGA touchscreen, a 1.4GHz CPU and 14.4Mbps HDSPA connectivity. It is meant to imply wonder - meaning the handset has a balance of style and performance. Galaxy M stands for magical while the Galaxy Y stands for Youth. The Youth devices are also meant to be the budget devices.