Interface Builder is most emphatically your friend. The compile/debug cycle in iOS is sufficiently lengthy that laying out views programmatically gets very tedious very fast.
Besides realtime previewing of exactly how your view is going to look, IB also helps you understand how your layout is affected by rotations to landscape and differences in view height between device classes (3GS/4/4S vs 5).
Nibs make it easy to tweak and adjust – and even to throw away and start fresh.
Most importantly, though – every nib you use is code you do not have to maintain. If a UI object has some part of its API deprecated, your nibs don't care. They're automatically up-to-date.
Can you do every fancy thing you'd like with nibs? Certainly not. But you can do the basic braindead layouts of labels and buttons there, and you're much likelier to get what you want the first time. There's enough tedious code to wrangle in iOS as it is – don't create more for yourself by rejecting a mature, useful tool.
edit: For clarity, though, by all means, enjoy this solid tutorial so you understand how to get your hands dirty when necessary. Just don't fear the IB.