When I look at my post, I see the full size image and no link on a thumbnail as I see with the others. I've copied and pasted the flickr image using bbc code. What am I doing wrong?
Nothing. There are two ways to post an image.
One is to include a link to it: it will appear full size, inline.
The other is to use the "attach" option, underneath the text box, when you compose the post: it will be uploaded and appear as a thumbnail. Clicking the thumbnail will either expand the image inline or open it in a new window; I've not managed to work out what factors cause the BB do choose which.
I prefer the thumbnail option. It saves time for people who have slow connections, as the full image is downloaded only if they actually want to see it. However, I've just noticed that it's not available on my iPad, which I suppose makes sense as there's no "open" dialog to allow selection of an image.