Grafana v4.3 introduces several significant updates, including a new Heatmap Panel and enhanced Histogram support in the Graph Panel, particularly benefiting users of Elasticsearch with its pre-bucketed data visualization capabilities. The release also debuts a MySQL data source in alpha version, allowing users to execute MySQL queries formatted as Time Series or Table Data, though it lacks certain features like templating and macros. Additionally, Grafana now supports a Health Check Endpoint for monitoring system status via HTTP responses and implements lazy loading for panels to reduce database load. Enhancements to Prometheus data source include Table Data format support, while the Graph Panel gains a new option for dashed lines. The update also addresses various bugs and improvements contributed by the Grafana community, showcasing their ongoing involvement in the platform's development.