MIT has a fairly well known undergraduate admissions blog. I think usually it’s just anxious high schoolers reading the posts, but some have garnered wider coverage and helped shape how the world views MIT.
The graduate school wanted a blog to cover graduate admissions as well, so starting this year there is a grad admissions blog. They collected the initial round of posts by running a writing workshop over IAP in January, which I was fortunate to be a part of. You can find my posts about some of what I’ve learned as a PhD student there: