This would be a smart purchase. I think it would be smart for DT to do though if they get a reasonable price. SprintPCS has 1900mhz licenses to cover the entire country, while at present T-Mobile does not. They both have relatively small networks compared to AT&T or Verizon Wireless' but combined they'd have more coverage than separately.

In future the alphabet soup would not be a big problem as it is now. At present, So now you have Sprint running iDen and CDMA, and T-Mobile running GSM. For data, Sprint has EVDO rev A, (2-3mbits/sec) while T-Mobile has EDGE. They've got 1 city with UMTS, but it's voice only, data is forced to EDGE apparently.

But, AT&T plans to go LTE. Verizon Wireless plans to go LTE. Alltel is looking to go LTE. US Cellular hasn't announced, but unofficially they plan to go LTE by 2012-2015. (See note 1) Sprint? WiMax.

So, DT just has to ditch wimax and go LTE. iDen's claim to fame is rapid, reliable push-to-talk, letting customers use the phones as walky-talkies basically. Sprint's already working with Qualcomm on "QChat" so they can do good push-to-talk via EVDO, then they'd phase out iDen. (AT&T and VZW both have push-to-talk but apparently it sucks). So DT should let that research continue, migrate the existing T-Mobile GSM network to LTE, and migrate the existing Sprint network to LTE. Instead of having to push GSM customers to CDMA, or CDMA customers to GSM (Note 2), you just get people to buy LTE phones over time and there's no more alphabet soup. (There should be both GSM+LTE and CDMA+LTE hybrid phones to cover the transition.)

Note 1: LTE is a fairly raw data transport, with calls being carried essentially via VOIP. It sounds like LTE is more a totally separate network than an upgrade of any sense from GSM, so existing GSM and CDMA networks are essentially on equal footing doing this upgrade.

Note 2: This is a touchy subject. GSM users decry the lack of phone options that CDMA users are stuck with. US CDMA users decry the lack of GSM coverage -- there's much more CDMA coverage than GSM in rural areas. Any provider that tries to switch from one to the other loses many customers.

The original reason I went with DT was so that I can easily use my phone when traveling abroad (mostly Europe). If they take over Sprint, I hope they keep GSM active. And why can't ATT & DT combine to offer good rural coverage in the US? It works fine in Europe, where the actual carrier in use can change every few km without problems. And I can buy a local SIM card to avoid/reduce roaming charges.