WARNING: If you have not yet read book 5, this contains a spoiler!
What do you think? A load of coincidences and guesswork? Or something more? It frankly wouldn't surprise me if J K Rowling had hidden something like this in her text - Harry's 'seven moves' is a particularly interesting 'coincidence' - but at the same time, you can read theories and find patterns in just about any text if you look hard enough.
It does parallel well with my thoughts as to what will happen in the future of the series, though my own theories don't come from careful research like the above. Mine are just second-guessing.
>_> I've worried about the fate of the Weasly family ever since the sequence with Mrs Weasly and the Boggart in book 5. 'Course, there's a perfectly innocent explanation for what she sees. A Boggart DOES show you your worst fears. But J K Rowling has proven time and time again that there almost everything in the HP universe, however small, winds up having a greater meaning.