I've spent some time recently trying to hunt down items for use in your Info.plist files. The natural place to look for these is the SpringBoard executable in the iPhone's Core Services folder. I ran this file through a strings filter, looking to see if I could find groupings of items that might work.

Several sections of strings jumped out from this search. I have included them below. Undoubtedly they contain items that aren't correct but I thought it would be cool to share, along with some comments.

SBDemoRole and SBIsRevealable - These are part of what I call the Macworld Suite, which are used to show and hide apps during a Jobs presentation. They've been played with extensively.

UIPrerenderedIcon - This one bypasses the clip and shine effect that SpringBoard applies to normal icons

UIRequiresPersistentWiFi and SBUsesNetwork - I've used these in applications that have to connect to the Internet.

UIRoleInfo, IsDefaultRole, UIRoleDisplayName - These are used by the Slideshow and iPod applications to make one application look like it's really two applications, like Photos and Camera, like Music and Video.

CFBundleDisplayName, CFBundleDevelopmentRegion, CFBundleExecutable, CFBundleIconFile, CFBundleIdentifier, CFBundleInfoDictionaryVersion, CFBundleName, CFBundlePackageType, CFBundleSignature, CFBundleVersion - These are the standard bundle prefs that are set automatically by Xcode.

PublicURLSchemes, PrivateURLSchemes, CFBundleURLTypes, CFBundleURLSchemes - These all have to do with launching apps by registering URL schemes, such as myscheme://

Here are some that I have no idea or just guesses as what they do

UIPriority
SBIconClass
SBMachServices
SBNoWatchdogs
SBMallocStackLogging
SBMallocGuardEdges
SBMallocCheckHeap
LocalizedApplicationNames
WidgetDisplayName
SBAppTags
UIMultiAppInfo

And finally, SBWidgetTag, WidgetDisplayName - References to widgets have been around for a long time, this is hardly the first thing that's shown up but it's intriguing that this appears among Info.plist strings in the SpringBoard executable. SpringBoard also refers to isWidgetApplication.

And on a completely unrelated point, a new SpringBoard preference is "SBVictoriaCapability". This appears among familiar SpringBoard preferences like SBFakeCarrier and SBFakeBars I have to try and test this out this week and figure out what it does.

I'm sure I've missed quite a lot of Info.plist items with my scan. So consider this a starting point rather than an authoritative list. Got more items to add? Drop a note in the comments.