So after toying with the Bold 9900 for a good 4-5 hours I've come to the conclusion that while the device is an excellent upgrade in terms of speed, and the capability of the device itself - OS7 has got to go. It's pretty much a pile of crap with lack of any true apps.
Coming from an iPhone 4, it feels like I've gone back in time. However, the typing has improved and one of my biggest complaints of the iPhone 4 -> the call quality was absolute garbage. The call quality on the 9900 is up there with the level of clarity you receive on a landline. Impressive. The ease of getting to what you need to get to communications wise on the BB is also great. The phone looks sexy as well, but unfortunately this is where it stops. The quality of the software and the speed of the iPhone 4 trounces this 9900.
Can only get worse for the BB fans once iOS5 comes out; if Apple decides to add an external notification led then look out.
Awesome phone itself, but the platform is the same crap I'd used on the Bold 9000 - that is to say, I feel like I'm back in 2008.
I'll be keeping the Bold 9900 as my girlfriend is getting my iPhone 4 as an upgrade from her 3Gs; but we shall see what happens in the future. If Apple ups their call quality and adds an external led...