Display:
While the Bionic does show pixelation and discoloration on some websites it's not something I am going to fret about. I don't really notice it unless I am staring at it. But who stares at their phones while doing nothing? I sure don't. I doubt anyone will notice as the high res may offset the Pentile display.
I can notice the pixelation on the home screens (grey widgets like the power bar and music player look like Super Mario Brothers). I don't see how one would have to stare at the screen "while doing nothing" to notice it. FYI, the Bionic has the same resolution as the Razr, so "the high res" doesn't offset the Pentile display. Granted, the Bionic screen doesn't look pixelated all the time. It is just very noticeable I say 25% of the time.
Battery:
Battery pulls for those of us who tend to tweak our phones a lot or have issues. Motorola isn't like Apple when it comes to battery quality. I know every battery has it's defective batches but I think Motorola has a higher rate than Apple. I've already seen some post where bad battery is the culprit. Not being able to swap is going to be an issue with RAZR users.
If you think about it logically, Moto will probably implement a button combo reset (like Apple has with the iPod) to replace the "battery pulling". This whole talk about defective batches of batteries and how Apple makes better batteries seems like hogwash to me. I've never had any problems with any NEW battery being defective for any device. Futhermore, I believe Apple and Moto get them from the same suppliers (FYI, they don't manufacture the batteries themselves). A better argument would be that batteries lose their charge capacity over time; therefore, the Bionic will never have the "permanent" problem of having poor battery life. But, as you mentioned, a removable battery is a huge plus for the Bionic.
Build Quality:
My Bionic is great. No flaw that I can see. My concern is the fact that it's thin and even having the above mentioned items may not protect it from certain users.
This is difference in opinion, but I think the Bionic is too big & thick. I mentioned this since day 1, and with the Razr announcement it confirms that Moto could have made it thinner/smaller but chose not to. Regarding your concerns on the Razr's thin profile, I don't see why there would be a correlation between the size of a cellphone and it's durability. I would think it's more of "how it's built" than "how big it is".
I'm probably keeping my Bionic by default. I would probably have to fork out an extra $200 for the Razr, and the Razr is not a $200 upgrade of the Bionic IMO. If the Prime was 4.3", I would have probably paid the premium because Moto phones have locked bootloaders, and Samsung phones are less buggy.