Pretty good time to be a Sprint customer... We know the SG2 is coming eventually as well, so we'll have top-tier options from at 'least three of the five major Android handset manufacturers (a G2X equivalent would be sweet, personally I could care less for Sony Ericsson tho). Sprint needs more variety tho, last year they set themselves up well w/the Epic and it's keyboard + the EVO... From recent leaks it doesn't seem like the next GS will be a slider so that means three 4"+ slabs, ho hum.
I'm partial to HTC, today's announcements regarding unlocked bootloaders restored my faith in them... Even if the EVO 3D ships with a locked bootloader they'll probably just leak en engineering bootloader that developers can use to work around it (like what happened w/the Thunderbolt, and early root methods for the EVO 4G even, you really think ALL those leaks are accidental? c'mon!).
There's a couple of things that could sway me towards the Photon tho... If it's significantly thinner than the EVO 3D I might bite, or if battery life on the EVO 3FD turns out to be abysmal (that's one thing Moto's pretty consistent with). The one other thing that could sway me towards Moto is if the Photon turns out to be a world phone, I heard a rumor that it'd have a SIM slot for GSM roaming, that'd be a sweet option (locked bootloader or not).
The GS2 looks pretty nice, it's definitely thin as heck and I don't think I'd mind the plastic feel too much (since I tend to use slim TPU cases anyway, so I don't care how the back feels/looks)... But I'm still wary of Samsung's lackluster track record w/updates. They seem to be doing better this time around w/GB already imminent for the GS2, but their inability to push US carriers to release updates quicker still worries me... And don't tell me the carrier/manufacturer relationship doesn't play a role there.
HTC/Sprint more than earned their keep w/the EVO... Pretty sure they released over half a dozen official updates, some pre-Froyo and several post-Froyo even (and GB is already leaking for most HTC pones, let's see when the Epic/Vibrant/Captivate get GB...).