Companies rarely die from moving too fast...
parislemon.com
parislemon.com
Also worth noting: for Windows Phone 7, Microsoft did actually ditch backwards compatibility in favor of "the new thing". And despite generally favorable reviews, it's not exactly burning up the sales charts.
In terms of ARM tablets, I assume that the only reason to have desktop mode is so it can run Office, however limited the features may be since it would take much too long to make it Metro/touch-friendly. MS isn't completely cutting the cord like Hastings is doing.
"though there's a difference between spinning your wheels fast, and actually moving forward."
Netflix is moving too fast in response to their subscription splitting. "Quikster" (sp?) looks like an overreaction to a brief, albeit significant, customer irritation. Rebranding the core product (it's long-term fame is for DVD rental, not streaming, even if the latter is the main goal) confuses people. "Hey, where did Netflix disc rentals go? Guess I gotta go to Blockbuster again..." I don't see this ending well.
So the downside to abandoning physical media is limited (they'll still own what's left of the rental delivery business) and the upside of staying in the lead of an increasingly competitive industry by focusing on on-demand video is huge.