Glare seems to be something of a personal issue. I would say that the Sony PRS-700 had too much glare and poor clarity compared to other e-ink readers. I loved the features but couldn't live with the glare and murky display.
The Sony Reader Touch PRS-600 doesn't bother me (there's some glare but not the loss of clarity I saw on the 700) and the Daily Edition 900 has perhaps just slightly less glare than the 900 and clarity that's very close to the Kindle 2, Kindle DX and Sony Pocket Edition 300.
-------------------- Lisa Gade Editor in Chief, MobileTechReview