AMD admits APU will hurt discrete GPU sales

At least the entry-level ones
Thomas Seifert, interim chief executive officer at AMD noted that, in the long run, some parts of the business will be cannibalized and the low-end discrete GPUs will be replaced with Fusion-type products. Of course, as far as AMD is concerned, it is not a bad thing as AMD wins both ways.
Of course, this won't happen over night and AMD will still continue to offer dedicated GPUs, even in low-end part of the market as it simply has an entire Intel based motherboard market that can still benefit even from a low-end discrete GPU.
More here.