Internet has made a big difference for kite boarding, but I would say it has had the same effect on windsurfing recently so I don't think the comparison is necessarily correct. Rather it is the differences in the sports themselves that are making windsurfing lag behind:
1) windsurfing is much harder to learn and not as enjoyable at first (in fact it can be a pain) so people give up quicker
2) kitesurfing, for the new guy, is a lot more spectacular and gets a lot of "wows" on the beach, so it attracts more people
3) I must admit kitesurfing equipment is a lot lighter and easier to carry around
4) Windsurfing, being an older sport, has an "old" image. People generally think its slow and boring, and that you need huge waves to have fun. However things have changed drastically. Take a look at a few videos on http://www.continentseven.com to see what I mean
1) windsurfing is much harder to learn and not as enjoyable at first (in fact it can be a pain) so people give up quicker
2) kitesurfing, for the new guy, is a lot more spectacular and gets a lot of "wows" on the beach, so it attracts more people
3) I must admit kitesurfing equipment is a lot lighter and easier to carry around
4) Windsurfing, being an older sport, has an "old" image. People generally think its slow and boring, and that you need huge waves to have fun. However things have changed drastically. Take a look at a few videos on http://www.continentseven.com to see what I mean