I think that my experience could be help you.
In python console with QGIS 2.4 (import gdal and import ogr work.)
in QGIS 2.6.1 the same command give this errors:
Traceback (most recent call last):
File "", line 1, in
File "C:/PROGRA~2/QGISBR~1/apps/qgis/./python\qgis\utils.py", line 460, in _import
mod = _builtin_import(name, globals, locals, fromlist, level)
ImportError: No module named gdal
well the problem is in the sys.path og python! Infact is missing the path to ogr.py and gdal.py
sys.path present in QGIS 2.4 'C:\PROGRA~2\QGISCH~1\apps\Python27\lib\site-packages\GDAL-1.11.0-py2.7-win32.egg'
in QGIS 2.6.1 is moved to 'C:\PROGRA~2\QGISCH~1\apps\Python27\lib\site-packages\osgeo' !?!?