I tried this out and it works like a charm. At first I got confused between "Highlighted word" and "Dictionary lookup of word", but I figured it out after some testing.
One feature that would be great, though I can't find a good way to implement at the moment, is to incorporate some form of 国語 lookup. For example, the word "何々" could be looked up in goo at
http://dictionary.goo.ne.jp/srch/all/何々/m0u/
If only there was some way to open a J-J dictionary in the popup instead. I suppose it would help if there were a no-nonesense 国語辞典 but I don't know any. Plus wwwJDic which provides the dictionaries for Rikaichan only seems to have J-E versions available. It's just a thought, but I think many people would get some use out of it.
One feature that would be great, though I can't find a good way to implement at the moment, is to incorporate some form of 国語 lookup. For example, the word "何々" could be looked up in goo at
http://dictionary.goo.ne.jp/srch/all/何々/m0u/
If only there was some way to open a J-J dictionary in the popup instead. I suppose it would help if there were a no-nonesense 国語辞典 but I don't know any. Plus wwwJDic which provides the dictionaries for Rikaichan only seems to have J-E versions available. It's just a thought, but I think many people would get some use out of it.