I have one too, and can attest to the quality of the display. It's like my X1's, except even better. The display alone makes it a worthwhile upgrade to existing users. Comparing the two exposes the 3G/3GS displays as the pitiful screens they always were.
The camera may have a decent resolution now, but they also have a nasty circle of slightly green tinted pixels which is a little disappointing. It's only really noticeable when you take a photo of a wall or similar subject, though.
The keyboard can't compare to a real one, but it's actually far better than I thought it was going to be. I'm really only missing the dedicated punctuation keys at the moment...
As for the grip of death, I switched to Telstra to attempt to reduce the effect of it. I haven't had a dropped call yet, but it did make both parties inaudible when I tested in a low reception area.
The LED is great, and is excellent with the Light app which automatically switches it on when started. Very bright and great as a torch.
Jailbreaking has allowed me to install SBSettings, OpenSSH, and custom SMS and email tones. I have no doubt I will find many other things to play with. It has not slowed down the phone at all.
The tethering is fantastic and works just like my old X1's did - easy, reliable and very fast (4.5Mbps!) and is much better than the P1 I've been using for the past couple months.
In much the same way as with my previous phones, I love the 4 and hate it at the same time (though for different reasons, obviously). It's not perfect but now that it has been upgraded and I have jailbroken, it will do the job nicely for the next 2 years. Overall though, I think I like the phone and can see it getting a crapton of use over the coming 24 months.