Try to structure your time so that you get the information you're looking for. Once that goal is accomplished, you can better afford to browse. See speakers as resources and gatekeepers. Presenters can also steer you toward other helpful sessions. Many presenters have presented in the past, so they can direct you toward relevant sessions and suppliers.
Speakers can be wonderful resources.
Develop a proxy learning team. If you're at the conference with a number of people from your organization, then you can divide up the sessions and make sure that the sessions you're interested in get covered. But if you're at the conference by yourself, the chances are that you're going to miss out on some of the sessions you'd like to attend but just can't. At the very first session, put together your own group of three or four people. Find out what sessions everyone is interested in, decide who will attend which sessions, and check back in with each other later in the conference to share notes and get first-hand reports.