Waiting on Kirk and Spock...

So watching the new season of Heroes-which is amazing of course, I have noticed that it seems that there is an abundance of appearances by the original members of Star Trek. First it was Sulu as Hiro's father, now Ohura as the aunt/grandmother of the Nikki's son, I half expect Denny Crane (boston legal-william shatner) to show up defending some unknown Hero character played by Leornard Nimoy. Any idea why they are showing up on the show?