Batchof08 as of i can picture is going to be a SONET (social networking)
I think trying to make an exclusive website is a bad idea. 
Three main reasons, 
<ol>
<li>you guys are going to start college soon so you prolly wouldnt have much time to maintain manage and update the website. </li>
<li>secondly you will have to promote and get your website popular. Next get people to register and get hem to be active. Thats a very tough task.</li>
<li>Lastly, there are already mega popular sonets like Facbook and Orkut which have powerful communities and tools. Why would people leave that, come and register on your site and be active?</li>

Not trying to be discouraging, but after having tried something similar and not succeeding in it has made me a bit more wiser. But of course i hope your site does do well and of course ill be glad to help anytime :)