Recently I bought an iPod touch. It originally came with OS 1.1.4 and as soon as Apple made the 2.0 software available (and downloadable), I upgraded.
While the new iTunes App Store is a welcome addition, I found most of the applications not very useful to me. While some like Remote, Facebook, Last.fm or eReader are awesome, I have yet to see applications on the store that fully unleash the power of the iPhone/iPod platform. For example, I’m waiting for a PDF reader that can fetch files from the local disk.
Here comes the power of jailbreak. There are so many things one can do with a jailbroken box. For example, with OpenSSH I can upload e-books to my iPod and bypass the limitations of eBook.app (it only likes e-books purchased from two web sites, but I have a few books that I legally downloaded from manybooks.net licensed under Creative Commons). I can also install Light HTTPd to serve PDFs locally that I can browse using Safari. It is very convoluted but it works.
Apple: if you read this, please lift all the absurd restrictions from the iPhone/iPod software and let people unleash the true power of this amazing portable platform.