Bit of a long post, but my finitial impressions.
Picked up my pre-order from Vodafone today and have used a Galaxy S2 previously (but only for about 15 minutes or so). I think the Sensation very good, but not great.
Obviously the screen colours are poorer, epecially if your not looking straight on, if not rediculously oversaturated like the S2 I was using which put me off that a little, though I have heard you can tone that down a bit. It is on the otherhand a noticeable amount sharper with the QHD screen, which was probably my biggest draw to it as I use my Desire for a fair amount of web browsing. To be honest, most people are going to prefer S2's screen unless you particularly want the sharpness.
Build wise it is better than the S2. The unibody back cover (kind of hugs round the main phone) and the added weight (while still lighter than my desire I think) do make it feel more of a premium phone. It feels good being slightly longer, thinner and more solid than the S2 (though I had no qualms with the S2's construction). Personally I found the S2 just a little too light, I like to feel I am holding a £500 phone. Again on the otherhand though I can see why many people light the feather light feeling of the S2 and would prefer it day to day.
Speed wise though as it stands it's a little up and down. Booting and browsing is very quick, no noticeable lag when zooming even with flash running a video at the same time. A few heavier apps load quicker and do feel generally a little faster to use than my Desire. Sadly though for some reason sense feels worse than my desire in some areas. Scrolling down the shorcut/widget lists feels juddery and slow to me. Also the main apps section is now in sepperate pages which looks poor, no more nice scrolling up and down through the list, it just jumps to the next page. Hopefully this can be changed. Also whether it's the animations or speed, scrolling through the main front screens seems to have a very slight judder to it, only very slight, but I expected better. So all in all, seems better at the more intensive tasks, but a little poorer at the easier ones. Will probably just wack Launcher Pro back on and that will sort the majority of this, as I would do on the S2 as I wasn't 100% convinced still by Touchwiz on that, though I think the S2 still handled scrolling better.
Camera is a step up from the Desire, the 1080p videos great and stills are better. Audio also is better via oth headphones and speakers, watched a few trailers on the HTC Watch app, looked really good and you could sell the sound hardware had been improved a touch of the Desire.
As side note, was a little shocked that even with the extra RAM, after clearing memory I still only had 220mb free, while my Desire would have around 170. Think something is up there.
Not had chance to try much else as at work, and can't give any real information on battery life yet. So as I said I do like the phone, but whether it's becuase the Desire was such a huge step up from my previous phones, or because Sense for some reason feels a little off (though an update will probably fix this) i don't like it quite as much as I though I would. Well t least until I put Launcher Pro on. If worst comes to the worst, I can return it next week and swap it for an S2.
