I do agree with you, but they still have both their switch line and the Enterasys switch line (it's not branded Enterasys, but the product line is still there). That purchase was almost three and a half years ago. In fact, they're still releasing new products in both lines. They have, however, released EXOS (their switch OS) for the original Enterasys line. They also announced the continuation of the WiNG-based WiFi business from Motorola/Zebra. To be fair, they did already have a history of working with both of those companies. Their original 802.11g Extreme-branded WiFi was made by Enterasys. There were some 802.11n AP's in that line, but that was later in the product life cycle. The follow on product for full 802.11n was made by Motorola.
A large part of the reason for this is that they don't want to alienate existing customers of their products, or customers of the product lines they've purchased. I do think that the lines will merge, I just think it'll take longer than it traditionally does with mergers and purchases. They are definitely starting to do that on the switch/router side of things between their original gear and the Enterasys gear.
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