I think Samsung missed the chance to be more open. They draaaaaagggged their feet with froyo, completely bungling the whole ordeal, and squandered a HUGE chance with the HTC locked bootloader fiasco. If they had gotten a release out (even a semi-borked one or leaked build with source) that the community could have rallied around, it would have been much easier to take advantage of HTC dabbling in locked bootloaders. Instead they dropped the ball. Now HTC has felt the backlash and recovered. They might lose a few customers at launch on the Evo 3D but they will get them back when/if they update it to be more open.
Samsung earned a lot of respect from me by releasing the source before EB13 was actually rolled out, so that I was running a custom overclocked ROM before my friends with un-rooted Epics had froyo. But it was very very close to too little, too late, and past the point of squandered opportunity.
That said, I still think the Evo 3D is a gimmick phone, and will be taking a wait and see approach for the next 6-8 months.