Well if your warranty statement says it'll void it then it will. But for example on the Galaxy SIII there's an application that enables you to reset your device fully. With no traces of root.
WWDC will most likely debut a new OSX update. Rumored is the 10.9 update codenamed "Cabernet". It is to expect that Apple will slowly but surely migrate all their platforms together, merging from both sides in.
http://9to5mac.com/2013/04/29/apple-to-update-os-x-with-new-power-user-features-more-from-ios-later-this-year/
Samsung announced its third generation Galaxy Tab with a 7' 1024 x 600 display. It is a mid-ranged tablet unlike to Galaxy Note 8.0. It will be launching in May.
It is equipped with a 1.2 dual-core processor, 1GB RAM, 4000mAh battery, Android 4.1 Jelly Bean, 3MP rear camera, 1.3MP front facing camera. It comes in 16 or 32 GB storage variates, expandable.