Yes, lots of carriers are now giving out bottles of water as part of their premium J or F inflight service, usually in advance of sleep time. This is a safer and more convenient way of having a wake-up sip to quell dry mouth, than having a full glass of water precariously set between you and your seatmate.

The bottles I've gotten on AC, Cdn, CO and other carriers have been 500mls, not full litres.