Okie, I'm back.
Adobe's flash is being dumped in a big way. While a lot of HTML5 tech was driven by Adobe back when they first started the standard, Flash has become overly expensive to run on the front and back end of browsers. Users and especially web developers are favoring HTML5 now due to it's efficiency as well as having no need to have a front-of-the-house plugin in order to play videos or content. While some developers will still use Flash, these developers are dying out in droves.
For those of you playing back 1080p or 720p content on the iPad, you'll probably notice no difference on the iPad itself but I'm pretty sure that you'll notice slight stuttering when Airplaying 1080p. It looks like 720p will be the format of choice for most iPad users over the next year since Airplay/normal home wifi networks just can't support such huge streaming numbers without affecting the entire network. I would say about 90% of people using the iPad won't be able to tell the difference between 720p and 1080p videos. The difference is very slight. However, when blowing this up to more than 48 inches on a 1080p display, the differences will be more severe where I think about 60% of the population won't notice the difference.
I'm suggesting that "power" users using the iPad with MKV video use Goodplayer and AVPlayerHD in order to play their movies HOWEVER, expect to lose your battery life about 1/3 as fast so your total playback time will probably be in the range of 4-5 hours of playback on full charge. 1080p content will look choppy because the iPad's CPU is not enough to offset the data rate of 1080p MKV compressed in whatever crappy codec. If this is a major issue to those of you that want to play MKVs, I would suggest the Nvidia Tegra 3 processor which is 4+1 cores and will have enough juice to push the video through. This however will also decrease battery life pretty harshly. Last time I checked on the ASUS Transformer Prime, I eked out about 5 hours of playback before the main battery was toast. The Transformer Prime also doesn't support surround sound so if you're looking to do AAC 5.1, you'll be sorely disappointed. If the iPad Goodplayer app had hardware acceleration support and built in the codecs to be decoded by the PowerVR chipset, we could probably playback the MKVs much better but at the current rate, I don't think Apple will do that and until Android tablets/devices start having better hardware acceleration, the balance of quality and performance are going to be an issue. So for anyone looking to stream MKVs with H.264 1080p video with AAC5.1, you're going to have to use a full Intel chipset meaning at least Core 2 Duo in order to pump out this decoding.