For me a good photograph is one which 'speaks' to me in some way. The same applies to art. Some supposedly great photographs or pieces of art just leave me cold, whilst I can be intrigued by a casual snapshot or amateurs painting.
I disagree that great photography is work that I'd choose to hang at home. You might see a great news picture but you probably wouldn't want it on permanent display. There are many images I can recall in my memory. Go along to the National Theatre in London look at the exhibition of press photography - plenty of good images that fall into this category.
Then there are the more banal photographs. Again they can be technically perfect in every way. In their own right they are good photographs but they only serve a limited purpose, be it a shot for a holiday brochure, a postcard, product shots, family portrait.
As for street photography I'm a big fan - this is also important work from a social documentary point of view. Look at John Deacons work now and what were probably considered mundane images at their time are now a fascinating record of the time. The term 'street' covers such a multitude of subject matter however. Look at
www.in-public.com for some examples of good street photography.
So, leaving aside the technically good, what constitutes a pictorially good photograph very much depends on the personal taste/preference of the viewer IMHO.
Regards