The paper Artificial General Intelligence: Concept, State of the Art, and Future Prospects (2014), by Ben Goertzel (one of the people that are really still very interested in AGI), surveys the field of artificial general intelligence (AGI), its progress, approaches, mathematical formalisms, engineering, and biology-inspired perspectives, and metrics for assessing AGI.
Just to give a little bit more context and whet your appetite, let me briefly describe the different approaches to AGI (section 3, p. 14).
symbolic approach (which is based on the Physical Symbol System Hypothesis; examples of this approach are ACT-R or SOAR),
emergentist approach (aka sub-symbolic, i.e. the use of neural networks, and similar sub-symbolic models, from which abstract symbolic processing/reasoning can or is expected to emerge; so examples of this approach is deep learning, computational neuroscience, and artificial life),
hybrid approach (a combination of the symbolic and sub-symbolic approaches; examples of this approach are CLARION and CogPrime), and
universalist approach (examples of this approach are the AIXI and Gödel machine).