Neat idea by Fabs. Just to prove her point, I need to go back to the beginning of 2008 to find any images of a House Sparrow in my files. This goes back to my Rebel XT days! I rarely photograph House Sparrows, not because they are not pretty (they are), but because I see them 99% of the time on houses, feeders, fences, pavement, etc... This one posed nicely on a "natural" perch (garden vegetation). Looking back on the exif this was taken on the very same day I joined BPN:).
This works. Sparrows are always welcome. The composition is strong. HA is nice, good eye contact. The only points I might suggest would be: perhaps a bit of a burn on the perch the saturate for contrast; maybe mask the BG and apply a touch of 'gausian blur' to accentuate the motion of the snow and soften for effect, blend as needed. Good image. ;)