Stephen Stohn (executive producer and Linda’s hubby) commented on the Official Degrassi website (will never link to them) that Degrassi: The Next Generation will be renewed for a sixth season by CTV. Probably the last season, though. (IMHO) The cast is getting older and shows do not last as many years as they did like Friends (what an awful show!).
They are filming their MOW or a Theatrical release in July of 2006, perhaps indicating an end to the series.