These latte cups are so much more.  The double walled glass keeps hot things hot and cold things cold.  Think beyond latte, think ice tea, smoothies or cocktails.  Slow down the ice melting process and don't worry about setting it on a coaster, no sweating.  I personally prefer drinking out of glass rather than plastic too.  
Durable glass makes them dishwasher safe; no scratching or chipping.