As long as Apple is not sharing data / information with these third party cloud services ... hum... in fact ...

One of the reasons I never use third party stuff. :)

Heck, it is one reason I take a jaundiced eye towards a lot of FIRST party stuff, too! (As a user)

Note: My personal surfing (via noscript)0 does not allow cloud connections by default or any scripts. Much quieter, more privacy control, and certainly a lot FASTER. HOWEVER that is my private side. As a webmaster I avoid all those things as much as possible and for my sites that works. For the other sites that require more interaction/scripting that this strategy is a nightmare and loss of income.

Avoid the third party as much as possible, do all "in house" at first party (that's "you") and the white list for example.com most blockers are willing to allow will not impact "the biz".

As for the cloud ... you and your users are giving up all kinds of data to a third party, period. And that is by design. Third parties are not your friends or partners... and if you read the TOS with these folks you will find out how much they are not friends and partners. First clue: if you have to fork over money, they are not a friend or partner. :)

.... and if they give it away for free, run for the hills because that won't last very long!