Silly Groose. And for a moment he looked like he was going to do something smart for a change.
So, what's happened since the last Skyward Sword update? Traditionally, after the first three temples you get a sort of interlude wherein large amounts of Plot happen and you get a collection of minor quests before the next temple. Here, the grand revelation is that Zelda has travelled back to the past and Mysterious Sheikah decided to blow up the time gate as well (Mysterious Sheikah seems to like blowing things up, especially in ways that are unhelpful for me). Fortunately there's another time gate, but unfortunately I can't open it yet. And for added fun, merely getting the gate to appear has unleashed the Imprisoned.
Which is a giant mass of scales and teeth that apparently is some unspeakable horror from long ago. It reminds me a bit of the moon from Majora's Mask - it has the same single-minded aim of destroying everything with absolutely no reason why it wants to do so. It's a very different beast to Ganon, who usually has some sort of reason behind his plans for world domination (in Wind Waker he has actual backstory and motivation, which is something of a rarity for a video game villain). Anyway, you don't so much defeat it as seal it back into the bottom of the pit until the next time it escapes and it counteracts your increased health and items by itself gaining a level in annoyance.
The other grand revelation is gaining access to the thunderhead and discovering the Isle of Songs, with the also traditional sliding (or rather rotating) block puzzle thrown in your way. As a nice touch, people in Skyloft do pay attention and say different things after you open the way to the thunderhead. They still have no idea about what's really happening, but it's little things like that which make a nice change from the usual totally oblivious NPCs.
Anyway, if I remember rightly the next step is the first Silent Realm, which I recall being equal parts creepy, scary, and awesome. Onwards!