I’ve moved! Have decided to follow the example of others (including @ProfBrianCox) and dump Twitpic for sharing photos via Twitter. Why? Because their current Terms of Service makes it clear that uploading anything to their site gives them an automatic, exclusive license to share your content – royalty-free – on a WORLDWIDE basis (see the 4th paragraph under ‘Copyright’).
So, since people have recommended this place, I thought I’d give it a whirl. IN YOUR FACE, TWITPIC!!