I wonder if this is simply reflecting the change Strathmore have made to more and more plastic bottles rather than Hilton actively changing anything. See this page for some further info:

http://www.strathmore-water.co.uk/our_commitment/

I tend to get one bottle of each (still and sparkling) in UK Hiltons, obviously once you go abroad the brand changes and you get different things in different places. For example in Germany, I find you see Apollinaris http://en.wikipedia.org/wiki/Apollinaris_(water)

which is quite good and popular there.

In the US or Canada, well, it can be a very mixed bag. Mostly, in Canada, people do drink water from the tap and it can be very good so drinking bottled water is a concept reserved for other countries or trendy people (very broad brush strokes here forgive me)...In the US, it tends to be rocky mountain water which I can accept but Dasani is rubbish and I would indeed rather drink tap water than that. (Coke should stick to soft drinks and leave water to those that know what it is!)

For the record, this thread does remind me that when you travel quite a bit, small things do indeed get on your nerves...especially if you stay in one brand quite a bit. For the occasional traveller, they are just happy to travel and don't notice or care what amenities, water, or other points are done well or not as they have little reference to compare to...however, for those that are in hotels night after night, well, if that second bottle of shower gel is missing or only one type of water is in the room on return...

All a matter of degrees...OP, I agree that I like glass bottles better and the water does taste better to me, however, it is a reflection of the times that many companies are moving to plastic as less expensive and cheaper to ship, 'more environmentally friendly' somehow! and small things do make a difference when you are staying away a lot. My tip: stay in a different chain where you get no benefits once in a while...that brings the focus back immediately (what? I have to pay for internet? What? I have to pay for breakfast? Where are my free drinks and snack? What? I don't get a drinks voucher? There is no lounge (or I can't access it!) Where is my exec floor mouthwash amenity? No slippers? No bathrobe?...

Its what I do when I start to get jaded and sweat the small stuff...and then the next stay in that Hilton or other brand I have status...brings an 'Aaah, good to be back...