This is an interesting snippet from the Qsonix page detailing how they get around the cover art challenge:
"Cover Art Cache Management � Remote Pro uses an intelligent caching mechanism to store a copy of each of the album covers in your music library. These files are stored in the iPad�s internal memory/disk system (like photos, music or videos) and dramatically increase the speed and performance of the application. The app will automatically cache (store) these images as necessary as you use the app, however you can use the �Populate Covers Cache� feature in the system menu to be sure that 100% of your albums are cached on the iPad. Depending upon library size and network conditions, this can take several minutes. Pressing the �Clear Cover Cache� will likewise delete all of the locally stored (cached) images. This can be useful if you need to free up storage space or re-cache your cover art."
No real magic there and a pretty straightforward solution that certainly could be used by the Sooloos team. Seemingly, if art is stored locally, that should dramatically reduce the amount of data being sent back and forth regularly between the system and the iPad. That should allow it to function much quicker and with far less lag. It may not be the ideal solution, but it seems pretty reasonable.
Jeff