On RSS, I follow some book bloggers (that has diminished over time as blogs overall have but some persevere) and then things like Book Riot, The Mary Sue, etc. I also get newsletters from some publishers, and thus at times review copies.
Professionally, we have access to CHOICE reviews, plus we also check some academic journals (I am an academic librarian), but my public library brethren mostly like also check things like Publishers Weekly. (c)