Media companies are expanding rapidly, integrating broadcast television, cable, radio, newspapers, books, magazines and the Internet under their roofs. Five conglomerates control most prime-time TV programming, and one company — Clear Channel — dominates radio. Yet, in the paradox of today's media landscape, consumers have more choices than ever, although critics say too many choices are low-brow offerings like “reality” TV. Meanwhile, newcomers — such as satellite radio and Web bloggers — keep sprouting. Now, as media companies push to grow even bigger, a nationwide debate rages over whether there's enough diversity of content and ownership. In June, the Federal Communications Commission relaxed its media-ownership rules, but growing resistance from lawmakers threatens to roll back the sweeping changes.