I see that the proposed lambda expressions can omit type annotations on the parameters. Does that mean that Java 8 will have at least some limited form of type inference?
If they will be based on anonymous inner classes, then yes, they'll capture the variables from the surrounding scope. Those variables however will be 'final', which means that you can't re-assign them, even if their values are still liable to side-effects (e.g. setting fields, mutating collections, etc).
They are not based on anonymous inner classes (the implementation is likely to be much different) but they have the same restrictions as BDFFL_Xenu described.