I have served espresso to many different people and (usually) small groups. I gradually realised that many guests are strongly influenced by "presentation." Cups are the primary element of presentation for espresso!

I live in an area with many consignment antique shops. Over several years I acquired several dozen different demitasse cups, most from china patterns. When guests are in my home and we are drinking espresso in an informal setting, I ask guests to go around and find a cup that they like. From watching what different people choose, I get an idea about what type of cup "goes over" well, and what "goes over" like a cement cloud or lead balloon.

When the occasion is slightly more formal I have several sets of 4 or 6 that I use. I try to match the cups to the guests.

The demitasse cups shown below are from three of my sets like this; perhaps they show the extremes.



The Wedgwood "Black Florentine" pattern on the right seems to have a tendency to elicit comments! Dark monochrome patterns like this seem to go naturally with espresso. The stark simplicity of stainless steel, as in the pattern on the left also has a certain appeal.

Even when one makes espresso just for oneself, the flavour of the espresso often seems to be infuenced by the appearance of the cup!!! I have to confess to being especially fond of "Black Florentine."

One can find truly amazing cup styles by looking through standard china patterns, far more than the ones commonly sold in conjunction with espresso equipment. The price can vary dramatically depending on the pattern and the source. Even rare patterns are often inexpensive at consignment antique shops.

Cups definitely affect the taste and the overall enjoyment of espresso. But fine china is suboptimal for espresso in my experience, and we've stopped using our Wedgwood, Suzy Cooper etc (current and antique) after decades of buying every cool cup I saw. We've used only Apilco espresso and cappuccino cups for several years now. They're thick and have a fairly high specific heat, so they stay warm and keep the coffee hot. The surface finish is very very smooth, and they wash extremely clean (which seems to help keep the crema rich and the taste consistent).

I once figured out that my wife had tried a new dishwashing detergent because the crema was thinner than usual and didn't run smoothly and uniformly down the walls of the cup as I drank. So we experimented, and those that leave everything "squeaky clean" do let the coffee taste come through without alteration or addition.

I also prefer cups with smooth internal contours for espresso. Sharp angles between the sides and bottom of a cup seem to me to hasten dissolution of the crema and reduce mouth feel a tiny bit. So we give our guests the cups we've found to best complement the coffee.

Vessels are definitely the jewelery of the beverage world. I love me a good vessel.

I serve my guests espresso in DeLonghi glass double walled espresso glasses, because the crema adds a lot of visual *wow* factor which I too have noticed affects the positive perception of how good the espresso is in their minds.

I myself prefer the taste of espresso from small standard 50ml ceramic cups and it is difficult for me to drink espresso out of anything else.

dominico wrote:I serve my guests espresso in DeLonghi glass double walled espresso glasses, because the crema adds a lot of visual *wow* factor which I too have noticed affects the positive perception of how good the espresso is in their minds.

I use the Illy "nude" cups for the same reason and get the same reaction. Most people who have tried making espresso at home seem amazed that I can get more than 1 mm of crema.

I don't know why but the sight of espresso in the double-walled glass is off-putting. I have no good reason not to like it, but I really don't.

I think maybe it's because I love the contrast of crema to white ceramic so much.

I would mostly agree with you actually; I find them off-putting when being served to me, because I think "this espresso is about to be too hot". Ceramic mugs do a much better job of cooling the espresso to my preferred drinking temperature, where it stays hot longer in a double-walled glass.
said, as a visual piece of art that other people are about to drink, I like the elegant look of the espresso in a glass because it shows off the layered-ness of the drink.