Due to fixing Bug 250179 by default plasma-workspace package have python flag disabled . This cause gmail-plasmoid stop working . First of all gmail-plasmoid very popular itself but also I suspect that there are range of other plasmoids that use python . So IMHO need set IUSE="python" for plasma-workspace. Reproducible: Always
Do you have some links regarding Plasma applet popularity that could back your suggestion up? I understand it's purely users preference but I strongly disagree with IUSE="+python". I mean avoiding "mandatority" of pykde4 dependency was one of the reasons to drop python USE flag from the profile.
I made some investigation . To detect popularity of gmail-plasmoid I use http://kde-look.org/index.php?xcontentmode=70x77x78. According it top10 by download plasmoids don't use py .( I detect this by download each plasmoid source and search it for *.py files - not sure if this is enough to say for sure ) . top10 by download starts with 70000 downloads and finishes with 18000 while gmail plasmoid have 11600 downloads . Also I found pyweather plasmoid with 4000 downloads .
Well, there really are a lot of plasmoids based on python scripting... I'm already looking forward to fixing the dependencies. (Personally I'd suggest re-adding python useflag to the kde desktop profile, but I know that this would somehow go against the spirit of things...)
I guess this is one of the cases where neither possible decision is ideal. Let's rather leave python off by default and fix the dependencies everywhere, such that all python plasmoids require plasma-workspace[python].