not mover, forgot the name liao
no ibluetooth for me, no jailbreak

If it's THAT easy for the developers then they would have done it in the first place.

It's not that simple as it's not just involving application or software for bluetooth transfer. If you don't have the protocol to begin with then there's no point to write the application.

Whats missing from iPhone is not the software but the most important part, the bluetooth protocol/stack. It's like you want to build a house but you don't have the plan to do so. Apple did not implement the bluetooth stack in the iPhone to deter such application to be created in the first place. They have a policy of not letting people share copyrighted stuff especially thru the normally practice phone owner i.e. bluetooth transfer.

What iBluetooth did was implement it's own bluetooth stack (which have to pay royalty to the stack owner and it's not free or open source) and integrate it with iPhone bluetooth system. Now that only applies prior to fw 3.0. Since 3.0 is a major firmware design change, the iBluetooth app is not entirely compatible as it was made for f.w 2.2.1 and below.

Hope that answer your Q on why it's THAT hard for developers to come out with app for Bluetooth.
p/s - I was about to write something sarcastic but held back. Bulan puasa la katakan.