Another hidden fee with be the fee to keep your current number. When the FCC mandated that wireless carriers have the capability to port numbers, the FCC said that carriers are allowed to charge a fee to recover porting costs. This fee can come from either your current or new carrier. So if your old carrier is trying to charge you a fee, see if you can talk your new carrier into absorbing that fee. It won't always work, but it is worth the try.

Even if you don't take advantage of number portability, many carriers are charging anywhere from 55 cents to $1.50 each month to customers to recoup costs. Check your bill to see how much you're being charged. You'll see the charge in the fees section of your bill.

Also note that you'll probably have to purchase a new phone. Yes, you may have the coolest phone on the block with all of the neat bells and whistles, but it won't do you any good if it's sitting on the shelf because your new carrier doesn't support it.

Here's why. Phones in the United States work on different networks such as CDMA (Code Division Multiple Access), GSM (Groupe Spiciale Mobile), TDMA (Time Division/Demand Multiple Access), and AMPS (Advanced Mobile Phone System). Let's say that you're currently with T-Mobile, which uses primarily a GSM network. You want to switch to Sprint, which uses a CDMA network. Since the carriers use different technologies, you won't be able to use the phone that works with GSM on the CDMA network.

Even if you switch carriers that use the same technology, carriers tend to support only the handsets that have been tested on their system. For instance, Sprint and Verizon both use CDMA networks, and Sprint's network might not support your Verizon phone. Check with the carrier you want to switch to and see if they support your current handset.

A few more important suggestions
Still want to switch carriers? There are a few more things to look out for as you go through the process of changing carriers.

First and foremost, do not terminate your current services before initiating service with your new carrier. Your best bet is to contact your new carrier and they'll start the porting process by contacting your current carrier. There is a transition period, and it's important to ask you new carrier how long the process will take.

If you use 911 during the transition, it's important to be aware that the dispatcher may not know the location or the number you're calling from. Be sure to tell the dispatcher at the beginning of the call your location and phone number.

We're entering a new era in the wireless industry and it's important to be as well informed as possible and feel free to ask questions!

ZATZ Senior News Editor Heather McDaniel is widely acknowledged as a leading expert on the converging handheld and mobile telecommunications industries.