Yes, I agree ASICminer is probably approaching 'bubble' status -- that's why I'm willing to sell a few shares
While probably not worth >10% of existing coins, I believe they do control over 10% of today's hashrate (and growing!)
Last check they were around 20% total hashrate. It's worth 150 million. I'm not sure if they give out 100% of profits, but based on last weeks dividend/profit the P/E ratio is 78, I believe.