Wow every time you demo Sketchblock a number of new features have crept in!
This time it's the saver plugins. Very nice. 
Yes export and import plugins are a useful new feature. The old datatypes based import / export is still present as a fallback.
Currently writen import plugins are:
info.skimp - Loads Amiga Icons - both unslected and selected images as two seperate layers.
openjpeg.skimp - Loads jpeg 2000 variants (.jp2 .2k etc) which allows import of HDR colour data for the first time.
Current export plugins
info.skexp - Saves a project as an AmigaIcon (if replacing an existing icon TOOLTypes etc are preserved) some restrictions apply (project must be two layers at most with equal size and no more than 256 in size)
openjpeg.skexp - saves as jpeg200 .jp2 format support 8 12 16 bits per channel, quality and alpha support
png.skexp - saves as PNG with or without alpha (deeper depths may be added later)
jpeg.skexp - ordinary jpeg - adds quality control not available in the old PIL based export script
ppm.skexp - PPM files. Mainly created as an API test but potentially useful if you want to script with netPBM...
ilbm.skexp - uses datatypes internal but allows 24 or 32bit ilbms means I can export ILBM for use as previews in Wordworth without need to convert them from 32bit (WW7 only supports 24 bit at most) then I can print to EPS from SB as well for the final high res print version in WW7
