Most of their services are still working fine for me.
The announced change has already been deployed, and was designed to ensure compliance with our API terms of service with as minimal disruption to app developers as possible. My understanding is that there are no further changes planned, so you shouldn't expect anything else from the api to change in the foreseeable future.
If what we've seen since yesterday is how it's supposed to work, then I think they may be using two levels of rate limiting:
- user-level rate limit: for scrobbling and loving tracks per IP: daily limit
- app-level rate limit: for retrieving images, album, artist info, etc.: seems using a very short time window and working again if the usage from the app falls back below the limit.
As they don't explicitly state that they will no longer allow any access to images, etc. and those services are still working, they may be just trying to minimize the impact from abusive usages by introducing those rate limiting.