It has about 10% of the global laptop market - and that's growing - making it the 4th largest single vendor, and it has about 35-40% of the global tablet market.

That looks pretty healthy to me.

Note that because most enterprise software is now web based ( ie moved to the data centre as you have pointed out ) - a lot of the corporate Windows only lockin has gone - so I'm seeing a steady rise in Macs in business.

What's not healthy is the desktop market ( apple laptops outsell desktops like 10:1 ) - but that's whiles that's more marked in the Apple space, it's largely an overall market trend. ( Overall desktops are about 20% of total shipments ).

So Apple will only be in trouble in this space if the laptop ceases to become wanted - and that's all about the interface - some apps are better with keyboard and mouse/trackpad and a bigger screen. If all that goes away and we just talk to our computers then I'd argue that Apple are better placed than Lenovo to weather that one.