The lack of an sd-card will be an issue for many users, however I personally do not store more than 8-16gb worth of media on my device anyway. It slows it down tremendously.
However, according to the article I read about the tablet,
The Amazon Kindle Fire Killer is out: Asus Nexus 7, now we have a tablet with 1GB of RAM, and NVIDIA’s quad-core Tegra 3 SoC processor. This will be great to stream video and work twice as fast than most tablets can currently.
I definitely want to get my hands on one to try it out myself.