87% of current pending reviews were submitted either yesterday or today (i.e. in around the last 24 hours), there are three pending reviews that are taking longer than usual for various reasons.
Reviews are definitely not slow at the moment, but what you may be seeing is a developer saying their resource is pending review and then their submission being rejected. In this situation it may look like the reviews are taking longer than they really are, but we're waiting for the developer to submit a fixed version in that case, so we can review it again.