will sim cards continue to be used in wireless phones?

Hello Beezoboar,

In short, the use of SIM cards is based entirely on the technology used.

The long version, there are two major technologies used to deliver cellular service in the United States, GSM and CDMA. Verizon doesn't use SIM (Subscriber Identity/Identification Module) cards because they use CDMA (Code Division Multiple Access) technology, rather than GSM (Global System for Mobile communication).

Below are the backgrounds and descriptions of different technologies and standards used.

GSM is a standard developed by the European Telecommunications Standards Institute (ETSI) to describe protocols for second generation (2G) digital cellular networks used by mobile phones. (1st generation networks were analogue). GPRS (General Packet Radio Services) and EDGE (Enhanced Data-rates for GSM Evolution) were standards developed to allow mobile data access. The personal information associated with service (the phone number, account number, etc.) are stored on the SIM card. Making GSM phones, generally, more universal. (Of course, the frequencies used must match. Carrier locks also prevent use of any network.) About 90% of the world's mobile telephony networks are GSM. 

A SIM card contains its unique serial number, international mobile subscriber identity (IMSI), authentication information, temporary information related to the local network, a list of the services the user has access to, a PIN for ordinary use, and a PUK for PIN unlocking. 

CDMA is a digital radio system that transmits streams of bits and allows multiple radios to share the same frequencies. This allows more handsets per tower. (Unlike TDMA, which divides the signal into time-slots, and alternates between them to use the same frequency. It is used more commonly in GSM.) cdmaOne (IS-95) is a standard that was developed by Qualcomm to describe 2G digital networks. The current use of CDMA is a third generation 3G technology, CDMA2000. With evolution from 1XRTT to EVDO. 

One of the primary differences the typical user may notice between CDMA and GSM is the use of SIM Cards.

With GSM, ETSI decided to go with a removable integrated circuit to store the account information. Qualcomm, on the other hand, opted to have the account information, authentication, etc. programmed into the firmware of the phone, thus eliminating the need for an additional removable integrated circuit. In the United States, this CDMA method is still in use. However, more recently, in some countries, such as Japan, an R-UID (Removable User Identitiy Module) is used. It is similar to a SIM, but is used for CDMA rather than GSM.

Further Development and why new Verizon and Sprint (CDMA) phones now have SIM cards.

UMTS and LTE were developed by the 3GPP based on GSM. UMTS was developed as 3G technology and LTE was developed as 4G technology. Neither of these are included in the ETSI GSM standard. Shortly after the development of UMTS, ETSI partially handed development of SIM applications to 3GPP. Since LTE is developed by 3GPP, the technology requires the use of a card similar to a SIM, called a UICC (Universal Integrated Circuit Card.) As such, CDMA handsets that have LTE, also have a UICC slot.

Regarding Cloud Storage 

Verizon doesn't use cloud storage for programming. As stated above, the programming is stored in the firmware. They can program the phones and update the PRL (Preferred Roaming List) through OTA (over the air) updates. Address books, etc. are stored on the phone's internal memory.

That being said, Verizon has introduced a feature called Verizon Cloud. Users can download the back-up assistant and backup their contacts online. (You can also have your contacts back up to Google's cloud, Apple's iCloud, Lookout's cloud, etc.) 

Cloud storage isn't new though, neither is saving of contracts. AT&T has offered AT&T Mobile Backup on select feature/messaging phones in the past. AT&T also offers their own cloud service called AT&T Locker. Users can download the AT&T locker application to their smartphones and back-up their contacts and media.