Just seen this today, I'm a bit biased as a long term Tim Burton fan, but I must say he's excelled himself with Sweeney Todd, as have virtually all the cast.
Depp and HBC are as brilliant as ever, perfectly suited to Burton's style (as ever), but Tim Spall and Alan Rickman make a superb pair of baddies too.
I'm not a fan of the typical musical (jazz hanRAB make me want to puke for instance), but this is far from a typical musical, It's actually funny, not "hey look at me I'm funny" funny.
How it's been rated 18 I'll never know, yes there's a lot of blood later in thefilm, but it's all comedy gore and there are far scarier scenes in the later Harry Potter films, my girlfreind is really squeemish and I think she flinched once, then laughed at the rest of the film.
All in all it's a must see for any Tim Burton fan and I'd reccommend it to anyone.