[citation][nom]whyso[/nom]Tegra 4 will have at most ~70 GFLOPS.Most low end gpu's have about 250 GFLOPS (hd 4000, gt 530) and will have trouble running crysis.[/citation]
What I was saying is not so much from a technical standpoint but from a consumer standpoint. If the resilience of 7 year old consoles and the high unit sales of Wii have taught us anything, it's that most users don't really care that much about graphics detail in games as much as they care about price, frame rate and fun. As long as the game plays smooth and is fun, it's going to work for most people whether it's 16xFSAA and 1080p or 4xFSAA and 720p or 20% lower polygon count or whatever. And tablet GPUs are progressing a lot faster than desktop and laptop GPUs, so whatever the difference is now, it'll only be getting smaller and less noticeable.
When mp3 first came out, it was 128kbps CBR at best and it still destroyed the CD, never mind that mp3s sounded worse. Laptops have been outselling desktops for 4 years, never mind that they're underpowered, have tiny screens, limited upgradability and limited battery life - they're just more convenient for most people.
When journalists talk about tablets being a PC replacement, they don't mean tablets can do everything a PC can do, just that for some (ever growing number of) people tablets can do everything they need. Once there is a critical mass of users who use ony tablets (email, Facebook, YouTube, casual games, web browsing), the OEMs and software companies will start putting more emphasis on tablet/mobile development and less resources in PC hardware, which will make PCs slow down both in technical advances and in sales, which will in turn raise prices and lead to even slower advances and sails, with tablets/mobile doing the opposite.