Dropbox is another easy way to get non-mobile photos to your phone.
Be cautioned, though, that large segments of the Instagram "community" strongly dislike the posting of DSLR photos on Instagram. (Which makes sense; there's a reason it's only a mobile app and not a stand-alone image sharing website.)
I am all for self-promotion and Instagram would be a great way to share photos with a large audience, but I respect its mobile phone intent. I suspect sooner or later Facebook will expand its website further in an attempt to kill Flickr...at which time I'll upload regular photos.