It has all the same libraries, Spyder, etc., and seems much more versatile, with easy package management and upgrades, and the ability to have different independent environments, e.g. one for Python 2.7 and one for Python 3: http://continuum.io/blog/anaconda-python-3
Plus it's cross-platform and works pretty much identically on Linux and Windows (and presumably Mac).
which has the additional advantage of being a portable installation.
If i'm not mistaken, the same people are behind WinPython and PythonXY.
WinPython has indeed been created by a core developer of PythonXY, using his experience from PythonXY .
Key advantages: (A) Portable version allowing indefinite number of side-by-side installations, (B) Both 32-bit and 64-bit versions are available for both Python 2 and 3.