I really would like to see some more types for saving like psd and pdf. BI doesnt have some important functions to be the #1 editor. So, as for me, I want to import file to Photoshop or SAI to correct drawings. Erm. Yes. Thx for attention.
robinthewalrus : +1 for the PSD format but why PSD ? Anyway the best interop/format is the .PNG ( you will not lose color precisions ). And the only workaround to recover your layer stack for the moment is the export each layer one by one in .PNG