I must say I'm pretty interested in picking up MUA 2, but I'm teetering on the brink and can't make up my mind. I've read a fair few reviews but they all seem to be written by people who've played MUA 1 and often concentrate on how it's very similar to the first or such and such a mechanic that they enjoyed is missing now. So I wanted to ask: As a MUA newbie, should I pick up this new version or just get the slightly cheaper MUA 1?

Welp, I'd say if you're a fan of Marvel Comics, and I mean a big fan, then get it. It's so steeped in Marvel comics lure that no matter what games you like to play, if you read comics then you'll probably love this. As for which of the two games to get, they both play almost exactly the same, except for a few changes and MUA2 has far better graphics. So I'll throw this out there to try and help you, in MUA1 you mostly fought a wide variety of villains, while in MUA2 you fight a wide variety of other heroes. So if one of those two options sounds particularly appealing to you I'd say go with that. Also, MUA2 let's you choose a side to follow in the storyline pretty early on, and while the levels are still similar after that, the story does get different. So essentially you can play MUA2 twice and still have a different gaming experience. 
So if you're just interested in the game mechanics, I'd say save the cash and go with MUA1, but if you're more interested in the story or graphics I'd say spend the extra cash on 2.

i need to know if I should add this to my Christmas list or not.

Thanks everyone (Hi Dave!). If I can hold out until Ryan's review then I will, but I fear I might cave in before then. Any more advice would be very welcome :) 
 
P.S. I like that obscurefan started his post with the word 'Welp'. It made me feel as if I was being given a lecture from a super-villain. 

Well, I played the first MUA without every playing any of the X-Men Legends games (MUA is a sequel of sorts to those games) and I loved it, UA 2 seems like is going to have much more stuff to do and is going to be freakin incredible so I would go for it if I was you.

"Well, I played the first MUA without every playing any of the X-Men Legends games (MUA is a sequel of sorts to those games) and I loved it, UA 2 seems like is going to have much more stuff to do and is going to be freakin incredible so I would go for it if I was you. "