I consider diversity vs one browser platform has its ups & downs.

Diversity Advantages is

• it promotes innovation by learning from each other.

Diversity Disvantages is

• that it is hard to develop sites that works consistently across all browsers.

One platform advantage is

• it's easy to standardize

One platform disadvantage is

• that it could slow down innovation

Until I figure out exactly "why" Microsoft making the move,
I won't know exactly what to think of it.

So my stance is that, I will use those ups & downs to my advantage.