iCloud, absolutely. I have had a me.com account for a couple of years, so it was a no brainer to make the switch. I like my contact, calendars, bookmarks etc all being synced to whichever device I happen to have. I didnt realise just how good it is until I did a clean install on both my macbook pro, and my imac, and everything just appeared, automagically.
Screen protector, Not at the moment. I will eventually buy a power support antiglare (which is what I have on my 3GS, and had on my iphone4 when I owned it) when it comes to Australian apple stores. I've found it very resistant to finger prints, whereas without protection, I need to have a microfibre cloth. I would not touch antiglare from any other company, its not working with the new screen, and I am pretty sure that Power support will do it right. Any others, use a clear one.
Questions are good
Best advice is explore the store and dont save your password on your Apple ID. If you have to enter a pass every time you want to buy it gives you that minute of breathing space to ask yourself if you really want it. Its addictive.