Do we still need to dial 1 for long-distance calls?

In this age of ubiquitous 10-digit dialing (3 digit area code + 7 digit phone number), cell phones, and unlimited calling plans, why must we dial 1 for a long distance?

Back in olden days, mechanical switches needed the 1 (as well as the second digit of the area code to be 0 or 1) to route properly. But that’s got to be way in the past what with today’s fully computerized telco offices.

I live in an area where we must always dial ten digits. Sometimes, area codes around here have phone numbers that are “local” and sometimes they’re “long distance” (requiring the 1). Problem is, I have no way of knowing in advance. It’s trial & error & frustration leading to messages like these:

> “We’re sorry. It is not necessary to dial a “1” for that number.”

- or -

> “We’re sorry. You must first dial a “1” for a long-distance call.”

Of course, this only applies to land lines. Cell phones have supported non-1 dialing in the U.S. for a long time. They automatically route long distance as needed.