I like Microsoft's localization efforts. Although I do use English version of Windows, setting my local to Croatia makes things much easier. There is something just natural about being able to use your number format, currency or even month names.
However, sometime efforts just go too far. If you are going to include day names in sentence style, do not include it in user's local ("e.g. every nedjelja"). Do it in OS' local (e.g. every Sunday). It doesn't look natural if different languages are mixed together.