Thanks for the input you guys.
jbhodj & Drake, thanks for pointing this out. After looking over the website it looks like it has promise, and likely very useful for what it is trying to accomplish. And it's useable today. =) I have some of the same goals and iGeocacher is a good example of some of what I want to provide with this project.
Along those lines, ReadyOrNot, I would want a portion of what I am doing to be usable as a cache manager, not just as a geocaching device. In that respect I think that iGeocacher could work reasonably well. I am definitely planning on allowing for cache management along similar lines.
fourbeer, I don't have much new information to you, it sounds like you know the answers already for these comments.
1) (and arguably 2b) I believe you cannot use the google maps feature unless you have an internet connection. I have an idea of how to get around this, but that will be some work and probably won't make it in version 1.0. I'd like it to, but we'll see. I think this is across the board for the iPhone and google maps. One of the benefits and downfalls of the iPhone platform is it assumes you are always connected. Especially in this case that may not be true.
From what I gather in 2, 2a and 3 you are speaking as if you regularly go geocaching for upwards of 6+ hours at a time. I know that this happens, is this the exception or the norm? Most that I know of only get maybe 3-4 caches in a given session. Inherent with the iPhone are limitations on using it for a full time GPS for long periods, and I don't think I can gear my application for that market because of that. I'd love to be able to have better answers for solving these issues, but it's a hardware limitation. If you do outings for that long the iPhone isn't your platform, plain and simple. I did have a good idea that this wouldn't be the end all be all of GPS's, but you make a valid point even if you're not meaning to -- this application should be geared more towards quicker sessions than long term GPSing.