[Captivate General] Dungeon47:
For anyone considering making the switch, I thought I would give some details on my experience having recently done this myself.

I had an iPhone 3G for about a year before I finally decided to jailbreak it and play with extra features. This led to all out phone modding with my 3GS, and finally the decision to move to Android for even more customization and utility. Here, i'll compare the experience I had with either device for inquiring minds contemplating a similar conundrum.

Jailbreaking and rooting; these words mean essentially the same thing: you gain full access tot he device's file system. There is, however, a distinct difference in the end result. With the iPhone, you typically jailbreak by running a utility that uses a software (or in some cases hardware) exploit to essentially exploit your way in.

Almost all of these will then install Cydia, a type of App Store that is not policed by Apple, and offers apps that only work on jailbroken devices because of their need to access parts of the file system that are typically restricted. From Cydia, you can download and install free and paid apps, and even gain access to black-market sources like Install0us where you can download pirated versions of paid apps.

Cydia contains what I consider to be the staple, or common, jailbroken apps. A few are:

MobileSubstrate: an underlying framework that provides an interface for the phones hardware that is common across many apps.

SBSettings: an easily accessible menu for controlling various functions, and displaying status information (wifi toggle, internal IP address, etc).

Winterboard: a theming app that essentially creates a layer on top of the existing UI to substitute a custom element for a standard one.

There are many others, many of which have been superseded by Apple's own improvements to their OS, such as Backgrounder for multitasking. The entire experience of theming and loading unapproved apps had a very under-the-table feel to it, and it was often difficult to find exactly what I needed, if even possible.

The upside of the iPhone with this is the nearly invincible nature of its systems. Barring hardware failure, or trying intentionally to do it, I can't see how it is even possible to brick an iPhone 3G or later. No matter what you do to it, you can restore it from iTunes and start over.

Android was a very different story. The initial path into rooting and flashing was scarce and difficult to follow at first. I heard a bunch of terms that I had no meaning for, and found it difficult to make sense of it all. Fortunately with the help of a few kind souls here on XDA, I learned what I need to know.

The rooting and modding experience did not have the slightly criminal feeling to it like my experience with the iPhone. I knew neither Apple nor Google was going to bother at all if I wanted to mess with my device; there was nothing to hide. The rooting process was very simple once I understood it, and using ADB from the Android SDK (I'll give details later) made the whole process feel comfortable with good directions. Adding non-market apps was a breeze with the Side-load Wonder Machine.

Finally I decided to try a custom ROM the day that I saw the leaked Froyo beta. Everything else had gone very well, so I felt confident as soon as I learned how to test 3-key download mode and found it successful. I had initially intended to try Cognition, but a recommendation for Assonance made me change my mind. Again, with good instructions, I flashed Assonance 3.1 with great success and have been enjoying the many benefits of custom ROMs since.

Thanks for reading if you've stuck with me thus far.

TL;DR (the experience broken down)

Rooting

iPhone: A full package process that is railroaded for better or worse. Even in the jailbreak community, you have very little options with iPhone. Some folks like--or need--it that way.

Android: At once it feels a little riskier at first, but if you play it safe, you'll find this just unlocks a door to more options.

Unapproved Apps

iPhone: Cydia, Rock, Install0us. What you see is what you get, and just pray the developer of your favorite apps doesn't quit. It can be hard to pay for things without paypal.

Android: It literally could not be easier. You don't even need to root first: http://www.androidcentral.com/sideload-android-apps-all-you-want-sideload-wonder-machine

Theming

iPhone: Tedious or slow; pick your poison. You can either manually replace each UI element yourself, making backups of the originals just in case, or you can use Winterboard, and deal with the performance hit. The plus side is that once you get the basics it is pretty standard across the board.

Android: Theming in general is much easier with LauncherPro, Desktop Visualizer, OpenHome, or ADW; but if you want to do the really detailed things like skin the dialer buttons, you are looking at something quite a bit more arcane than simple PNGs in iPhone. Some of this can be overcome by flashing various themes, but it still isn't individual control.

Functionality

iPhone: For functions not built into iOS, you have a few choices which aren't really choices as much as must-haves. Beyond that, you can just hope someone will happen to make what you need, and it will be maintained through iOS updates.

Android: The sky is the limit, but you need to be able to fly the plane. I can't make apps; no idea how, but the majority of my wishlist for the iPhone was built into Android 2.2 out of the box..

Reliability

iPhone: As I said before, a hardware failure is pretty much the only major dead end, but any piece, even the battery pretty much means a new phone.

Android: Software reliability will take more work than it will on the iPhone. You don't have iTunes making a full restore backup every few days, so you'll need to take the initiative yourself to make copies of pictures and music, and backup apps.

I know this ended up being a little scatterbrained, but hopefully it will help someone out in making the right choice for them. Remember, the iPhone is like James Bond: he is the best there is at doing exactly what he was meant to do. Then Android is like MacGyver: a little rough around the edges, but given the right tools he can do anything. One isn't better, they are just different. Choose what is right for you, stay in school, and don't do drugs.