If you've ever been to Rome, the odds are pretty good that you've been to the Trevi Fountain. It's one of those places that, even if you don't particularly want to see it, you pretty much have to in order to fend off the people back home who will otherwise go 'How could you visit [city] and not see [really famous thing]?' It's the reason I have four blurry pictures of a tiny Hollywood sign on my camera.
That said, it always sucks when those attractions fall into disrepair. That's why the Hollywood sign isn't the Hollywoodland sign. That's why so much time and energy was spent in New Hampshire to prop up a crumbling natural rock formation. (A rock formation which collapsed anyway.) That's why you've always got a couple scattered cranks saying that we "have to" tear down Wrigley Field. And that's why the Trevi Fountain is looking at a restoration project: it has pieces falling off of it. It's been 20 years since the last restoration, and it's clearly due for another now.
The crumbling has been notably acute this year. What's thought to have happened is that the harsh winter Europe just had, particularly a snowstorm that hit Italy in February, caused snowmelt to seep into the pores of the fountain, weakening the structure. ('Winter', America. It's called 'winter'. That thing we didn't have this year.) It seems a bit odd, blaming a fountain's structural-integrity problems on what amounts to unforeseen water damage, but not all parts of all fountains are meant to have water rushing over them at all times, and besides, melted snow can easily refreeze- and expand as ice- inside the pores.
Hopefully they can get it repaired with minimal fuss.