I'm looking to buy a bike in the new year, but there's so many choices out there - any advice?

It depends what type of riding you'll do and where.  If you want to go off-road, then you need a mtn bike.  Road bikes are either built for speed (racers) or more comfort (tourers).  A good compromise for mtn bike comfort on the road is a hybrid.  A good bike shop should be able to give you good advice.

An inexpensive mtn bike can be a good choice for around town and off road.  Your better off going with a good name brand with no shocks than a cheapie with shocks - unless you're riding rough terrain you won't really need them, and they make the bike much heavier.

I have a mtn bike i use around town and it's great.  It's a GT, was only about £300 but I've had it 3 years and it's never needed any work done or anything.

I have one too - feel like i can use it about anywhere.

I guess my first reply was a bit unopinionated.  I do think that most hybrids fall between two stools - neither one thing nor the other.  For around town and a bit of trail, a decent MTB w/out shocks is actually a very good all round choice.