Like others said, uptime for a registrar barely matters. For an important domain, I don't want anything to change, and if the registrar is down, nothing will change, so that's good.

What MarkMonitor can provide is things like facilitating RegistryLock, which makes it even harder for changes to be made. And account reps that know what's going on. I hate working with account reps, but if they're knowledgable and easy to work with, it's ok.

They do some trademark monitoring (thus the name), if you want to get your own related app taken down from Google Play :p (I'm not bitter, it was amusing). And presence services if you need to hold a domain in a weird location that wants a presence, they can probably arrange it, which is handy at times.

I'd love to know more details on this incident, MarkMonitor had a bulletproof reputation as a registrar that won't fuck up. Godaddy doesn't, but then I didn't realize they had taken over the contract for .us