They seem to have increased friction after going through a dishwasher. The unpleasant (to me) squeaky feel is probably slip-stick friction exciting resonance in the glassware. But why? What has happened to the surface of the glass to make it like this?
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A completely clean silica surface has a very high surface energy and a very high coefficient of friction. However silica surfaces adsorb pretty much anything at the least excuse, so glassware from your cupboard will have a layer of various molecules adsorbed from its environment, and this greatly reduces the coefficient of friction.
Dishwash powder is pretty aggressive, which is not surprising when you consider what it has to wash off. In my time working in the industry the powders used high concentrations of sodium and potassium hydroxide and would not only strip the glass clean but actually dissolve off a layer of glass as well. I believe current dishwash powders are less aggressive (not least for safety considerations!) but they will still leave the glass surface very clean and hence very high friction.
John Rennie
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