What is the main difference between MHP and proprietary middleware

After I have learned MHP for some time ,I am now thinking about one thing:

IF one proprietary middleware provider say OpenTV use Java and open its api,and make it open that any one can implement its middleware standard.Can we call it Open standard?

What I mean is,open standard middleware such as MHP only have 3 main difference with proprietary middleware as Below:

1:based on platform independent Java

2:any one can implement the mw stack for free

3:any one can get the api and develop app for free

AM I right?

[557 byte] By [ifaint_zhanga] at [2007-10-3 10:05:34]