I'm on the road (in Florida bad-dialup hell too) and was watching the basketball game in the hotel room, amused by the continual exhortations of the announcers to “Log on to nba.com” for one thing or another. You hear this usage all the time in commercials and promotions, but almost never among people who actually use the Web. I “visit” or “hit” or “look at” websites, I don't “log on” to them. But maybe I'm not giving them enough credit for subtlety.
The saying goes “Never ascribe to malice that which can be explained by stupidity” so I guess the most likely explanation is that the people who craft these hit-our-website pitches are people who don't actually hit web sites.
This is a little surprising - you think people in the heart of the media world would perforce be using the Net to get their jobs done. Is it possible that there is a community of people out there who are in positions of sufficient influence that they script the announcers on national sports broadcasts, but don't actually use Web browsers?
Alternatively, I suppose that this is language subtlely crafted to suggest that just visiting nba.com isn't good enough, you really ought to give them your demographic info and you haven't had the experience unless you really do “log in.”