It really varies from store to store, based on who's setting the department. Usually the stores that have a 3rd party company set their TCG stuff will be more prompt about being on time, but those 3rd party setters almost certainly won't be there at midnight. On the flip side, if they're only scheduled to come in once a week, the cards might sit there a while since the employees won't touch it.
For the stores that rely on their own employees, those employees who know/care about the TCGs and their releases (or are at least competent enough about rules to follow the dates on the boxes) will have the product out on the right day, possibly in the middle of the night since that's when a lot of stocking gets done. Stores whose employees don't know or care are the ones who set things late or early.
My local Meijer seems to be pretty good about following release dates. I've rarely seen anything set early and they're usually pretty close on time. Target's about the same, though I've never seen them set early. I've only been to Walmart a few times, but they always seem to be late. Those are just my local stores, though. As with all big box chains, results will vary.
