Consumers are free to stay with their incumbent utility - no one is forcing anyone to change suppliers.
Customers are also free to choose to work directly with an alternate supplier by doing their own research, but the problem here is that there are 40+ suppliers. Are you going to interview them all to find the best one? Do you have the time? Are you well versed in matters of energy deregulation? Be careful, some suppliers take advantage of the uninformed, or perhaps the company you choose might not be financially stable.
Thus, I recommend using a consultant such as Commercial Energy Consultants (CEC) that has been working with energy deregulation for the last five years. We have over 200 million kilowatts under contract and over 500 client relationships.
Why use a consultant? As a consultant we have the knowledge to garner the lowest bid from available suppliers. We regularly contact suppliers, asking for bids on a consumer's particular residential/commercial need, and then deliver the lowest bid. This process takes the hassle out of working directly with these suppliers.
Our job is simple: Bring our clients the lowest bid. Since we are paid by the supplier, our clients do not have any cost in choosing a different provider.
For example, I met with a busy school administrator who had been given the task to deregulate by her board. She had received a couple of solicitations in the mail and talked to one supplier, but realized there are more than 20 suppliers approved by her state. She was already too busy -- what was she to do?
She called CEC and hired us to find the supplier. It took about a week and it didn't cost the school a penny. CEC delivered the low bid and saved the school thousands of dollars.
A recent new option in the market is "municipal aggregation". Simply stated, a City puts all the residents together in a group and bids them out to a supplier. Muni-aggregation is mostly a residential offering and usually comes in as an opt-out offering, where you are given a rate but can opt out of it if you like.
I personally view muni-aggregation as "force feeding". I think the consumer can do just as well, and still maintain the flexibility to choose who they want to do business with, and not be force-fed by their City.