In many countries old school telcos are under fire from new competitors. For instance AT&T in the US is fighting threats from VOIP services provided by both large scale (almost as monolithic) providers such as Comcast but also the likes of Skype, Vonage and MagicJack. Although there are some issues (what happens when there's no power, 911 calls and quality) providers such as Skype offer as wide a range of services for a fraction of the cost (I've spent less in a year on my Skype account than even Comcast wanted per month for a landline)
Even the cash cow for many Telcos - Mobile - is under threat. Unlimited data plans and fairly ubiquitous hotspots in Starbucks, Borders, McDonalds or FON coupled with mobile versions of Skype and other VOIP clients has the potential to threaten voice revenues (and of course embedded messenger solutions eat into Texting revenues).
Although I still can't quite get over the US habit of charging me to receive a mobile call (as well as charging the caller) I'm not too disappointed with the quality or cost of the service - though T-Mobile really does need a 3G data network soon as GPRS/EDGE isn't that spectacular (coming from Australia I really miss my Three 3G data plan).
The thing that kills me with mobile though is roaming and international calling. Back in the last century before planet wide partnerships and telco empires (eg Vodafone/Verizon or T-Mobile in the US, UK, Germany etc) you could see reasons for the telcos to charge like a wounded bull but in these days of cheap and ubiquitous alternatives making the experience of roaming painfully expensive (and difficult) is just stupid.
I'm traveling in the UK at the moment with a T-Mobile phone. It's taken me a week to get a SIM unlock code (ironically for 10 quid I could have walked into one of a dozen shops and had my phone unlocked in minutes) so I was left with the option of either using their roaming rates or finding an alternative. Although the phone claimed to recognize and log me in to T-Mobile Hotspots I wasn't even able to use my "unlimited" data plan here. I ended up borrowing an unlocked phone and a pre-paid SIM with data at one pound a day (not from T-Mobile so they lost out there - just because I was annoyed with them!) and I used Skype for most calls.
The day that a telco realizes the value of not being seen to gouge a customer who wants to show loyalty and use their service in countries where their logo is commonplace... I'll switch. Especially if they can come up with a solution that allows me fairly seamless communications without needing to resort to Skype or similar to get a better deal eg a local number that people can enter my US number as an extension and get redirected so neither they nor I get penalized for making calls in country and international calls are shipped over their backbone so I don't get penalized for phoning home.
Looking at what these companies claim the cost of acquiring a customer is trying to recover that from my in a week when I'm overseas is silly. After this trip I have lost any loyalty towards T-Mobile and when my contract expires (or is economically viable to break) I've no real reason to remain a customer.... an unintended consequence of short sightedness.