A few of the news publications here have given it 2.5 stars out of 5 (which is a star for every hour!). This score is more or less correct, but you don't watch a movie like ROTF for quality cinema. You go to see robots bashing the fuck out of each other, which is something you get a fair bit of.
The problem is that it is still quite dull; the battles lack the real 'HOLY SHIT OH MY GOD WOW' factor which is what it rests on. And of course, Bidoof and Fox are back with the teenage love story thing thrown into the mix. And I'm still a dick about that, you know? We don't need no humans in our movies about giant robots!
For some reason, there was a LOT of Linkin Park in this movie. Loads. Everytime you hear music that isn't orchestral, that's Linkin Park. However, ROTF also had some of the themes from the first movie, which made me incredibly glad because I fucking loved the score. I also have to admit that there was a point in the film where 'The Touch' by Stan Bush looped in my head, which made it a very snicker-worthy moment.
The new Decepticons and Autobots look all very pretty and shiny, but ROTF made me feel as though they had no purpose. I was looking forward to an epic, huge Devastator battle.
The only characters that were really built upon were Megatron and Starscream. Which makes me wonder why they decided to change Starscream's voice for ROTF - I was actually perfectly happy with it in the first movie and read the sequel comics in his voice. I feel as though the more traditional Starscream voice does not suit him, especially given his stature and appearance. (Incidentally, the scene in which Megatron and Starscream meet again totally reminds me of Power Rangers: The Movie.)
Speaking of pointless, there's also a branch in the movie that is completely pointless and quite frankly, I think it was tacked in there to appeal to the teenage masses. I found the humour to be much too juvenile and tasteless for my liking, but I suppose that's how you target an audience.
What did this movie do for me? It made me respect Bumblebee. It also made me root for the Autobots. Also, ROTF contains the coolest incarnation of Jetfire ever. And All Hail Optimus.
OVERALL: Six out of ten broken Bidoof bones
EDIT: After watching it a second time, I've finally pinpointed the thing that really irked me about ROTF. The events from Reign of Starscream after never actually referenced or mentioned, other than perhaps the alien tattoos Starscream sports. It's like the Decepticons suddenly forgot that Starscream wasn't their leader anymore and just dropped what they were doing before going back to serve Megatron. What the fuck. I feel raped and cheated.