Devin - spot on with your carrier comment.
Exclusivity contracts with certain providers mean that you are limited depending on your current contract. Manufacturers such as HTC are fairly new to the UK, so that should bring some excitement to what was becoming a stagnant region, IMO, but it depends if they are exclusively on one network or not.
Sony Ericsson, Nokia and Samsung were too happy to attach a new plastic fascia to an old design, and fob it off to customers as something new. Then along came the iPhone to rattle everyone's cage. It's improved the selection of handsets from other manufacturers, as they struggle to compete. If HTC can start to make an impact and have the same effect, then that should be great for the consumer. However, it all depends on what sort of flexibility the contract providers allow customers to have.
I wouldn't be surprised if other big computer hardware / software manufacturers started getting heavily involved in handset manufacture, because phones are essentially now mini-computers (both smartphones and featurephones), and will continue in this direction for many years to come. Apple were still a niche company not so long ago, even though they had been in existence for the best part of 30 years. Two products changed all that, one of which was a phone.
The fact that the ubiquitous mobile phone handset covers such a multitude of demographics will be too much temptation for another big hardware manufacturer looking to improve their sales figures, IMHO. Choice is still a good thing, but even 15 new handsets per year isn't much when you consider all the people in the market. And how many of them are truly NEW? - are they a re-hash of old technology, or something genuinely new?
The iPhone WAS something fresh in a stagnent market, and I don't think we'll see its likes for a long time. But since the launch of the iPhone, it hasn't really changed TOO much externally or feature wise - Apple have sadly adopted the same predictable pattern as other manufacturers. Add a camera, increase memory, bring out a new colour scheme, software v1.2, add a better camera, add more memory, bring out another colour, software version 1.3 - yawn. zzzzzzzzz - if it wasn't for new apps, the iPhone would be a bit boring already.