I also heard from a fairly reliable source within Nortel that they are looking at dropping the BCM product line - that would be the 200 and 400. They are considering at the moment whether they will be introducing the 300 & 600, or re-designing an entirely new product and re-naming their SMB product line. The BCM platform is now over almost 7 years old. The only major change really is the change from NT to Linux, but the hardware is pretty much the same.
What I hear is that for Nortel to grow and compete successfully against Mitel, Cisco, and Avaya in the SMB market moving forward they need an architecture that can reliably grow to the 300 - 400 port range. Apparently the writing is now on the wall for the 200 and 400 - there should be an announcement in March 2007. The 50 still seems safe though - phew !