It looks like the current version of JOSM is modeless. It is a step in the right direction (more user friendly) because most text editors (like the one I'm typing right now) are modeless.

The problem is that unwilling users are be bullied into using something that "should still be considered an alpha release".

The good news about API0.5 is that it simplifies things by getting rid of segments. The bad news about it is that referential integrity w.r.t. relationships may cause endless frustrations for newbies who may not know how to delete ways created in error. And some of the ways have become part of the 'multipolygon' relationship during the conversion to API0.5, so this is already a real problem.