iCloud is no more or less secure than most online based services (in fact maybe more so than many). I've been using for quite sometime with no problems. Partucularlky with the Contacts lists which I share between an MBP, iPad and iPhone. Short of using it to synchronize those contacts lists, I don't know of any way to view the content of the iPad from another device.
You can read a bit more about iCloud here: http://www.apple.com/support/icloud/
It does require that the devices you wish to synch with are all using the same AppleID for the general Mail,Contacts,Calendar function, but you can choose wich services you wish to synch (just Contacts for example).