Which mobile phone should I buy?

With my T-mobile contract finally finishing yesterday, I am now looking for a new phone. However, despite having my N95 for 18 months, there is no obvious replacement.

Although there are Nokia phones with slight improvements, such as the N96 (or even the N95 8Gb), the improvements are not sufficient to persuade me to sign up for another 18 month contract. It is therefore necessary to look further afield, and at the moment I am thinking about O2's Xda Serra (a branded HTC Touch Pro):

Although it includes my main two requirements (i.e., touchscreen and qwerty keyboard), will I later regret not waiting for the N97? I have no way of knowing whether the N97 will be worth it, or whether it will even be in my price range. And at which point do you stop waiting? There is always a better phone just over the horizon!

Any comments or phone suggestions are welcome...although iPhone suggestions will fall on deaf ears.