I just renewed my passport, and it's now a shiny e-passport, but I'm not sure what that means in terms of international travel. Do all (major) airports tend to have e-passport gates for which my e-passport will work? Do I no longer have to queue to be looked up and down by an expressionless security officer? Is e-passport generally faster than the manual check? Can I do the manual check if the queue is shorter?

My next 3 trips are LHR, PHX and BCN.