DIRECTV (Nasdaq: DTV) is still going full steam ahead, stealing customers from the cable guys while fending off assaults from Verizon (NYSE: VZ) and its fellow telecom bandits. Satellite TV is a great business to be in right now -- but how long will the gravy train last?

First-quarter sales jumped by 14% year over year to $5.6 billion, outpacing the 13% annual growth seen last quarter. Likewise, the bottom line accelerated its improvement by nearly tripling, at $0.59 per share. DIRECTV achieved all of this while adding just 100,000 net new subscribers in the quarter, pointing to higher revenues per customer. CEO Mike White gives credit for his company's performance to "our differentiated and compelling suite of products and services offered throughout the Americas."

Chances are that DISH Network (Nasdaq: DISH) will present similar numbers on Monday while the likes of Comcast (Nasdaq: CMCSA) will gnash their teeth later on over dwindling subscriber counts -- even if their sales are improving. There's a changing of the guard going on here as the satellite specialists are taking the baton from the cable industry.

As pretty as the satellite picture looks right now, I still wouldn't buy any of these stocks today. The current rise to market-beating returns must end with a bang at some point, when the average consumer catches on to the rich choices of digital entertainment that are available now or coming online soon. Netflix (Nasdaq: NFLX) alone won't kill traditional broadcasting. Neither will Amazon.com's (Nasdaq: AMZN) movies on demand, nor Apple (Nasdaq: AAPL) iTunes or Hulu. But that's just a small selection off the frothy top of the onrushing digital avalanche, and I firmly believe that today's broadcasting model is destined for the scrap heap in a few short years.

There's no way to tell exactly when the next sea change will hit this industry, but there is no doubt that it's coming. I'm staying far away from cable and satellite TV stocks.