Over the weekend I installed the Developers version of iPhone OS 4 (one advantage of being an iPhone Developer), and I must say the multi-tasking is great, although unfortunately several of the apps I’d like to use and test it with haven’t released compatible updates yet… but regardless of that the I’ve found OS 4 to be very stable and responsive.
I’m positive multi-tasking will be a blessing in the not to distant future when updates are released, but in the meantime undoubtedly the biggest time saving and most useful feature thus far is the ability to organise and group your apps into folders! This has reduced my iPhone from around 15 screens down to one home screen with 17 folders!
But as I’ve said before… “Those who don’t keep their stuff in order, are lazy… while those who do, are too lazy to look for their stuff”