Eagle Ridge is available in two form factors (normal and SFF) and is effectively half of a Light Ridge chip. That means you only get two Thunderbolt channels (2 x 10Gbps bidirectional = 40Gbps aggregate bandwidth) and one DP output. Apple used the small form factor version of Eagle Ridge in its new MacBook Air to cut cost and save on motherboard real estate. The MacBook Air’s GPU also doesn’t support more than one external display so there was no point in using a Thunderbolt controller with two DP outputs.
One DisplayPort output. That means you can connect only one external display to the mid-2011 MacBook Airs. If you want to add that second monitor the only way as far as I know is to get a DisplayLink-powered USB graphics adapter.