What would you say makes RPG20xx superior over other free alternatives to RPGMaker? Such as the Wolf RPG Editor and RPGboss.
The answer to this depends on you, actually. In the end, you must answer this for yourself.. but I'm going to assume you are asking me this because you want me to answer as though it were my perspective.
It is true I can read Japanese, but it would take me too long to decode Wolf RPG Editor in order to evaluate it. It might be good, or it might be horrible. Japanese support will come to RPG20XX. If it works with Japanese text already, it would be coincidental. I still need to perform a series of tests first.
RPGboss looks as though it barely exists, is hard to use, and probably won't be finished. RPGboss is a good example that any RPG toolkit advertising "Open Source!" and "Linux!" on the front page over *a list of useful RPG features you are actually going to care about* is not worth your time. I haven't needed to refer to the many easy to use yet powerful features already implemented or planned for RPG20XX to answer this question. It is sad that you can eliminate many pieces of RPG creation software with the simple question "..but can it make RPGs?".
I also wrote a survey of other RPG creation toolkits here where I compare RPG20XX to the most complete projects out there: http://rpgmaker.net/games/2664/blog/12505/