They're also mostly 1366x768

The image quality and the "smoothness", aka response time, are equal to that of mobile discrete GPUs (FFS, look up. I've already posted that. Saying you've read what I've posted and actually reading it are two different things entirely). In both of those regards, Intel has a bit of work to do. Though a recent driver update has fixed some image quality issues that persisted with Ivy Bridge, they're still a bit away from discrete-level image quality.
So they're not bottom end anything. They're actually replacing mid-level mobile graphics cards already. AMD's 7660G compares roughly to a GT540m/GT630m while Intel is a bit behind, somewhere around the GT520m level.
Instead of going with your _____insert response here instead of reading the reviews_____, it might do you good to actually read the mobile reviews, specifically where the on-die GPU is concerned. The same scenario you're describing that you want on the desktop, discrete level performance that's actually respectable, is already there on laptops. You know... the segment of the market that makes up the majority of sales.