1) stream delivery rate not being sufficient where buffering pauses can occur - this is unlikely to occur most of the time if you are sufficiently close to the CDN server using those local connections but there was a good warning a few posts back to make sure you are using local DNS (otherwse you may be pulling from distant servers which might have problems)
2) video content not being fluid at the sub second level - this seems to have been acknowledged by Tim Martin as a known issue related to compability between providers that was supposedly close to resolution - I still see the effects on some of the content, more obvious on a larger screen, where every 5th frame is a static repeat of the 4th which looks jittery on panning shots - my bitrate viewer shows data belonging to the first 4 frames with nearly no data for the 5th - this can also vary during the game.
I could add a 3rd issue of the manifest files for the iPad stream changing where some of the rates seem to get dropped off. This is usually on a Sunday and they get more fully populated by the Monday. A quick check shows this can also be localised - this morning I had the latest stream missing 3000 but when I looked on some different Akamai addresses which I think are in Auckland this higher speed stream was there, I can't say for sure how the apps handle this but I would expect if is missing from the manifest it won't play that rate.
Every viewer will have slightly different issues and thresholds of where they become irritating. At least PLP seem aware of the issues.