I didn't apply to Berkeley or NYU, so haven't followed these super closely. Iirc, Berkeley has sent out lots of rejections and some acceptances, so no news could be implicit wait list, and maybe more news will follow soon.
Based on previous years, no news from Northwestern likely means a rejection or wait list is coming soon (maybe implicit wait list at this point). But the wait list is typically long, so I wouldn't hold much hope of getting off it. We haven't heard much from Columbia for PhDs (just a couple of interviews), so I'm not really sure what to expect there. No news isn't a good signal, but I imagine we'll hear more from them soon and wouldn't put it in the IR bucket yet.