Tens of thousands of people, of all ages, all around the world, were sitting down today to read the one book. The hype does get a bit wearing, but the fact that the world is getting this excited about a book can only be a good thing.
I couldn't resist joining the throng. It reminds me of the excitement of my childhood, when I'd found a new pony book from one of my favourite series, and I'd simply sit and do nothing until I'd read it straight through, then I'd turn back to page one and start all over again.
On most levels, The Half-Blood Prince is more of the same old Potter, which is no doubt exactly what its child fans want. The standard of writing is as before: simple and a bit clunky—how you'd love to get in as an editor to tighten it up and straighten it out; the story lines are getting a bit repetitive in their twists and turns - one lot of magic seems much like another to an adult reader.
But the world of magic has moved on with the age of its characters. It does, as reported earlier, end with a funeral of an important character, with the emotions of those watching fully described (no don't worry, I'm not going to tell you who is interred). This may well upset some younger readers. There does, however, seem to be less gory action than in The Order of the Phoenix.
Boy-girl relationships are a large part of the story (which is I fear certainly going to put off boy readers). These are, however, curious. In their depiction of early teen, confused, messy, ties lasting days or weeks, the form seems accurate, but they are bloodless and passionless. That might, from a charitable view, be a deliberate attempt not to lose the younger readers, but I'm not sure it will work.