Several things jump out quickly, but let's state the obvious ones. They provide a Flash component for Flash 8. Now it's cool that they provide a component (even if "installing a component is arcane), but Flash 8. Seriously? Clearly this is something written in ActionScript 2.0. Now it would be one thing if they wanted to provide some support for AS2 developers, but what about AS3? It just seems crazy for a brand new platform to not support the latest version of one of the two languages it supports. It would be like Silverlight only supporting C# 1.1.
There's also the issue of providing support for the Flash IDE exclusively as well. I guess with AS3 support only, this is all you can expect. The Flash IDE is not made for developers, it is made for designers. Flex Builder is obviously the choice for developers, though it has its drawbacks.
I didn't see if Meebo provides the source code for the SWC. If they did, it probably wouldn't be too hard to compile it for AS3. Actually you might be able to use the AS2 component within an AS3, I haven't tried that. Still, if you're going to launch a me-too platform, at least do it right.