As far I as know, Realbasic is the only one that tries to get the interface right on each platform. It also gives you the ability to compile for all of the OS's on your development OS of choice. (I think think that now includes Linux.)
Your link added two I wasn't aware of, but I'd be curious how they do with getting the interface right.
I think Apples Java has some hooks or tricks to get the OS X interface right, or at least close.
As someone mentioned, it depends on what kind of coding you are doing. When you move up to the GUI things get more tricky. Also, even at the 'command line' level, some low level feature may not exist on all of your targets.
Lastly there is the issue of stability. You may find that on the OS you are developing on eveything works as expected, but when you run your application on another system, certain odd bugs appear. The tool I use at my day job has had this issue. I'm about to 'port' our application for the second time. I've moved it from Digital Unix, to Sun Solaris, and now to IBM AIX. I expect a few issues. I've also had issues with major version upgrades at times. It could be one or all of the tool, the database, and the OS version.
If you go forward with this, please let us know in a few months how it is working out.