This deal will be a good thing for many of us. For Yahoo shareholders, they are getting a good price for their shares. For Verizon shareholders, the future looks good because this will be good for business. It is also good for advertisers because it presents a whole new mobile advertising platform.
No, Verizon's purchase of Yahoo's Internet business is not a good thing. Government regulations should prevent such conglomerations in order to protect consumers from monopolies and price gouging. More competition is needed in the communications sphere, not less. The combined company will still be too weak to compete with Google and Facebook.
In general, I don't like it when one huge company buys another big company. I think that a healthy amount of competition is a good thing for the market. Although Verizon and Yahoo provide different types of services, there is some overlap, so this will probably just result in higher prices.
If Verizon were to buy Yahoo's interned business it would give one company significantly too much influence and control. As a phone company there is no reason for Verizon to expand to take over Yahoo's internet business. Buying the business may be good for Verizon but I think that it would negatively impact customers.