I like the app, it's clean looking, fast and I really like the 3d buildings, but clearly it wasn't ready to be released to the public as a replacement for Google maps.
For the time being be patient, I'm positive that apple will make make improvements to it over time, but it really shouldn't have been released just yet.
I for one really don't miss google maps that much simply because I have never relied on it to get me around. I bought navigon a long time ago for all of my turn-by-turn needs, so again, I don't miss it. Heck, when I get my iPhone 5 I probably won't use the apple maps for turn-by-turn either. Just saying.