The discussion around 'Happy 10k Day' revolves primarily around the recent success of Comma AI, which achieved sales of 10k units of their latest model, the Comma 3X. Users express excitement about its autonomous driving capabilities, particularly in the context of Tesla users transitioning to Comma for similar features. Several commenters highlight the need for greater visibility and marketing for the product among traditional dealerships, suggesting hands-on demonstrations could boost sales. Additionally, there is curiosity about comparative rankings of self-driving technology between companies like Tesla and Mercedes, along with questions regarding international usage of Comma’s devices. Users also share their experiences with Comma AI’s technology, expressing both enthusiasm and caution regarding its implementation in personal vehicles. Overall, there is a blend of excitement and concern regarding the safety and practicality of autonomous driving technology, indicating a growing interest in alternatives to established autonomous systems.