According to several sources, the latest Android phone from Motorola "The DroidX" available on Verizon has hardware built  in (the eFuse chip) that will brick the phone if you mess with the bootloader.
This is akin to a car manufacturer designing a car the freezes the engine if you open the hood.

No one should for a moment even consider buying something designed to fail even if you do not plan on ever changing the boot loader.
Would you buy a car if somehow the manufacturer removed the option to change the tires or modify the engine. I personally would not.

Personally I feel that this should be illegal! It is only a small step away from designing hardware that fails the day the warranty is up.

What if there is a security flaw and someone can brick your phone simply by making it think the boot-loader has been tampered with? The trigger is there, and the failure is a hardware failure which is absolutely insane.
I predict that this will indeed happen and in a small way I hope it does to teach these companies a lesson. I empathise with all of the consumers who will be the true victoms here. So I urge you, do not even consider buying a Droid X.

What if Android comes out with a newer OS with new features and 1 year later for whatever political reason Motorola has still not released an upgrade. What if the never plan on releasing an upgrade?
In that case you would have paid good money for a device capable of being better than it is with untold new features, yet you purchased the designed to fail version and are forever locked in to whatever Motorola and Verizon officially release. Don't do it. Even if you never plan to install an upgraded OS or change the boot loader.

If you want to be locked in to a manufacturer get an iPhone. Seriously! If you jailbreak the iphone it is an awesome unix device with great open source repositories. If Apple bricks your jailbroken iPhone it is a software issue and is easily remedied by un-bricking it. One of the major arguments for Android has been that it is open source and the devices and OS have typically been Hacker (not Cracker) friendly.

My advice, get an EVO.
I made the switch and have been very happy with both the device and Sprint. Yes, I have rooted my phone, specifically so that I can under clock it and get extra battery life. As soon as the hacked Froyo firmware supports the camera I will give that a spin too, but will switch to the officially released version whenever it becomes available. That said, Sprint is extremely fair and open for example they let you use your phone as a wifi hotspot for up to 8 devices. They also do not charge for calls to any cell network, only landlines. Thanks Sprint!

Personally I am outraged at both Motorola and Verizon and will not consider ever purchasing anything from either company. I loved Motorola products until yesterday and had also been a happy Verizon customer before switching to an iPhone 2 years ago. Seriously, if Motorola released a time machine tomorrow I wouldn't consider it. I would be to afraid that it would self destruct because I chose to visit an unapproved place in time.