On the one hand there are essentially no new features that are interesting, and even iOS5 is pretty dull. I can't believe Siri will take off, much like voice control didn't take off with the 4 - novelty value but not much else. And this is good, because it means no real push to upgrade.
On the other hand my Dad has been talking about getting an iPhone for months, but is struggling with the price. I could sell him my 4 for the cost of upgrading to the 4S with O2, which essentially means it costs me nothing.
The benefits of the 4S as I see them are the improved power (moar power = good!) and the increased size (64GB). Even the latter is a debatable plus point, as my music and audiobook collection is 190GB, yet my various favourites playlists fit quite neatly into 32GB.
Also it will mean queuing at an O2 store, again. And now that the O2 store in Fleet has closed it means going somewhere bigger, no doubt even earlier in the morning. Bleugh.
Not sure whether to bother. T-minus 12 days.