I sent a mail to Kin-Man that we can't pass parameters from the
framework to the method-expression. So, we can now do:

#{bb.action(myparam)}

to call a method with signature:

public String action(String myparam) {}

but we can not do:

#{bb.valueChangeListener(myparam)}

to call a method with signature:

public void valueChangeListener(ValueChangeEvent ev, String myparam) {}

only with signature:

public void valueChangeListener(String myparam) {}

so what we loose is the ValueChangeEvent, which was provided by the
JSF framework as a parameter to the invoke-call in the
Method-Expression instance (we will only receive the parsed
parameters).

I already got mail by Kin-Man - he said this won't be included, we are too late.