[Update December 2020: While we first reported ESP32-C3 would be pin-to-pin compatible to ESP8266 based on the tweet mentioned in the post, the datasheets show both are clearly not pin-to-pin compatible, and instead it looks like the goal is to provide pin-to-pin compatible modules]
When we reported about ESP32-S2-MINI modules last September, we also noted Espressif teased us with ESP32-S3 and ESP32-C3 with close to no details. ESP32-S3 is expected to be a multi-core WiFI & Bluetooth processor with AI instructions/accelerator, but there were no details about ESP32-C3 at all, and we only found out it would be a RISC-V processor several weeks ago.
But Twitter user Johnny Wu posted a screenshot in Chinese and its translation claiming ESP32-C3 was finally released by Espressif Systems. [Update: The datasheet has been released. See comments.]
ESP32-C3 WiSoC is pin to pin compatible with ESP8266, works with ESP32 development framework (e.g. ESP-IDF), supports Wi-Fi & Bluetooth LE 5.0 connectivity, and integrates 400KB SRAM & 384KB ROM. It features a single32-bit RISC-V (RV32IMC) core @ 160 MHz, and consume as little as 5uA in deep sleep mode. Pricing will also be similar to ESP8266.
I could not find any information on Espressif Systems yet, nor much on other sources, and the text above appears to come from a post on Xueqiu, and the user also reported Espressif raised funds to develop a WiFi 6 FEM (Front-end module). Nevertheless, the news confirms some of the information available in the source code for esptool, ESP-IDF, and openOCD when looking for “esp32c3” string, some of which is listed in a thread on ESP32.com forums.
If the information is correct that means ESP32-C3 based RISC-V WiFi and Bluetooth modules similar to ESP-01 should soon be available for sale for around $1.
Thanks to Arnaud for the tip.