Paul,
John the Revelator wrote those words describing the new heaven and new earth having 'no more sea'.  I believe one of the most important things to consider was WHERE John was when he penned them.  He was on the Isle of Patmos, exhiled and ISOLATED from the rest of the world.  He was isolated from all of those whom he loved, his family, friends and from Christian fellowship.  The sea represents that isolation.  In the new heaven and new earth there will be no isolation or separation from loved ones in Christ.  The word specifically was the Greek word for the Meditteranian or the Red Sea.  I don't know exactly how the Lord will remake the world, but I'm sure it will be more wonderful than we can imagine, and there will be no more isolatin from anyone we love in Christ.
 
YBIC,
Kevin H.