In-game advertising would definitely be a good way for Rockstar to get some more cash. Like when your driving down the street or whatever, seeing signs for top stores and restaurants and stuff. I wouldn't mind that, but it's not a big deal.
I hope they release a PC version. It's probably the only way I'm going to be able to get Grand Theft Auto IV. I have a Play Station2 and a PSP, but my next-gen console is going to be a Nintendo Wii so I won't be getting a XBOX 360 or PS3 to play the new Grand Theft Auto games... plus the modifications and everything will definitely enhance the gameplay.
Referring to the whole "selling violent video games to underage children thing", maybe children that aren't mature enough to understand that they shouldn't go out on the streets and kill people, etc. shouldn't be playing it but I know a good load of people that play Grand Theft Auto, are underage, and haven't thought about that at all. I know there are some teenagers these days like it, but there are also teenagers that know the difference and are mature enough to play the games and I don't really see a harm in them playing it if they understand not to do it in real life, I'm one of them.
I forgot to comment on the Grand Theft Auto for Nintendo Wii portion of the article, so here goes. I really would like to see GTA for the Wii. Why not do something so it would require and work well with the classic controller? That thing would handle it better than using the Wiimote, or even using the Gamecube Controller. The Wii supports those two standard old-style controllers so I'd say they could customize Grand Theft Auto IV to work with those.
In conclusion, I really hope there will be either a Wii or PC version of Grand Theft Auto; preferably PC.