In order to redirect the user to the search sites, the user's Domain Name Service (DNS) settings are altered

said by TKJunkMail :

And of course they drag in the magical words "net neutrality" as if somehow using these words give some legitimacy to their complaint even though the concept isn't applicable at all in this case.

said by article :

It also raises the question of whether or not an Internet provider that automatically redirects a user's searches without telling them will also shape the results they do get, such as filtering their searches to get specific results.

[...]

Although Verizon opposes net neutrality, it has also said repeatedly that it would not block content or favor its own offerings over rivals--although it now appears to be doing just that.

said by TKJunkMail :

But they should make it opt-in instead of opt-out and then advertise it to their customers as a good feature to have.