I'm not sure how many things are ever really necessary, and if they are, the time-span in which they are necessary is up for debate. Twitter may offer an enhanced way to communicate, and ideally reach goals and make positive change, but it is only as necessary as the goals and changes. I'm glad language, paper, the printing press, radio, tv and the internet were developed, but maybe only because I'd feel left out if anyone else used those things and I couldn't. I don't want to consider whether the world is "a better place" because of any mass communication with a one-on-one feel to it, but since I've no choice in being part of a several-thousand-year experiment, I'll just be happy to go along with things they way they are rapidly evolving. Maybe temporary utility is all I'm willing to give credit for. Later, somebody smarter than me can wonder if Twitter was necessary.