Christopher mentioned not liking this aspect of Star Trek the other day, and I agree with him. Although I can accept that people attending the same classes at the Academy know one another, I have a hard time accepting that people working on opposite sides of the Federation could be best friends, or that the commanding officers of two random vessels would happen to have children named after their counterpart. I can certainly accept that specific groups of people may be aware of one another. For example, I'm sure Starfleet maintains various listservs that include all ship captains, all science officers, all engineers, etc, so it's possible that someone like Jadzia Dax (as a science officer) would have been familiar with Kathryn Janeway for reasons other than her commanding Voyager (but would never have met her in person), just as I'm sure that Captains Spock and Terrell spent countless hours deleting every spam email sent by Captain Styles about the Excelsior's warp-engines, without having suffer the indignity of being in the same room with him (pre-TWOK, of course). But I don't like the idea that Captain Picard has a friend on every ship, nor do I think it makes sense that every one of Riker's classmates would be on the verge of his or her own command at the same time that Riker would have. It may have simplified things from a story-telling perspective, but it doesn't add up.