God is in the habit of making technology serve the interests of his Son. The invention of the printing press seems calculated almost entirely to make Luther's Theses go viral. The onset of the internet seems another wave in this trend, as it has been mightily used to give voracious expositional preaching a wider listenership--and with the arrival of online video streaming, a wider viewership as well.
I would hardly minimize the exquisite fruit that has come of it. I myself owe much to the preaching of men I've never met. However, while these resources serve as great supplements to the spiritual health of believers, they can never, by themselves, be the full course meal of heavenly nourishment that God has prepared for you and I.
Preaching itself was primarily designed to take place at the local church level, where the preacher, to one extent or another, knows the people he's preaching to. As we've said before, preaching becomes more exactly the word of God to his people when it takes place within these communities, also known as local churches.
Another way of looking at this is to say that, in the local church ideal, no one slips through the cracks. You can rock out to Paul Washer sermons all you like but at the same time be living in sin (yes, even such a shocking arrangement is possible). However, you cannot be a real member of a local church and do so. This brings us to the importance of accountability within the church.
One of our Lord's parting commands was as follows: "A new commandment I give to you, that you love one another: just as I have loved you, you are also to love one another." John 13:34. This one another language hits a keynote that is carried through the New Testament and expresses the ever-important idea of the community of God's people. That's what we are.
In fact, if you trace out the one another commands in Scripture, you will find that it is quite literally impossible to fulfill them if you are not part of a local church. Every such apostolic command comes to us within the context of a local church, for that is to whom the great majority of Letters were written. These commands to love one another (that is in fact what they all come to in the end) help protect the individual believer from slipping through the cracks. Speaking the truth to one another, stirring one another up to good works, admonishing one another, all of these prods of grace (and many more) come not only from the pulpit but from the community itself (Ephesians 4:15, 25; Hebrews 10:24; Colossians 3:16). This aspect of accountability will serve not only to steer you out of sin but also encourage you to press forward, taking hold of the eternal life to which you have been called.