The big trend in cellular or mobile telephony for 2005 will be...gaming.

The reason for that has to do with the nature of gaming in the 21st century (as opposed to the 20th). It's online. (That's why the makers of this Lord of the Rings game won't at all mind paying the bandwidth charges on your download of that troll over there, in exchange for the above link, which acts as an advertisement.)

The point is that in modern online games the game itself takes place in an online realm, for which you pay by the hour. The download of the game itself is trivial. Many game makers offer free downloads. It's the old razor blade analogy (or the computer printer analogy) -- give away the razor and sell the blades (or the toner).

Why will this happen so quickly?

• The lag-time between Internet trends and mobile trends is going down as 3G networks and better phones make the two more similar.
• Carriers profit twice from online games, once when the game is downloaded, but second (continually) as the game is played. Mobile telephony is still metered, so unlike an ISP they always get a cut.
• Carriers can create entirely new, predictable revenue streams by selling "packages" of game minutes. Since these minutes are more certain to be used than talk minutes, and since they will come on broadband networks, they will cost more.
• Mobile phone carriers can use their control over their networks to control the content on games in ways ISPs can only dream of. Pro-censorship activists (many of whom masquerade as "child advocates") will applaud this quietly, while loudly condemning mobile game content anyway, to keep it from moving to "R" from "G".

What can slow this trend? Traffic accidents. The attention required for an online game is immense, compared to that required for talking. Someone's going to want to play while driving, and they are going to die.