Comparison with RR failure
This may be a much more serious failure, than the Quantas A380 RR failure. The reason the RR failure became serious, is that the turbune section is under the wing, and so the wing was peppered with schrapnel, causing multiple secondary failures. Which were heroically dealt with.
However, in this EA failure the entire N1 hub has fractured and the entire N1 fan departed (those 'blades' you can see are the stators behind the missing fan). And the N1 fan is deliberately positioned ahead of the wing to reduce secondary damage (which is why jet and piston engines poke out the front of the wing, on nearly all aircraft). But had this huge fan hit something on the way out, like the El Al 747 engine that came lose out of Schiphol, the secondary airframe and engine failures could have been catastrophic. They were lucky that the fan flew off without hitting anything (as it can fly off in any direction).
I see fleet groundings from this, as this may be a much more fundamental and serious problem, than the RR failure. The RR failure was a simple component manufacture issue, that leaked oil into a bearing and overheated it. So the rectification was to ensure that one small component costing a few dollars was manufactured correctly. A simple rectification. But why did a complete N1 fan fail and depart? (an almost unheard of failure). Could it have been something simple, like an oil pipe fracture starving the bearing? There is an amount of oil staining on the cowl, which may point towards oil loss, before the failure. Conversely, if this was a design problem in the strength of the N1 shaft, then all these EA engines will have to be grounded, for a complete redesign and overhaul.
Only time will tell.
Silver