I've found this memory across chats quite useful on a practical level too, but it also has added to the feeling of developing an ongoing personal relationship with the LLM.

Not only does the model (chat gpt) know about my job, tech interests etc and tie chats together using that info.

But also I have noticed the "tone" of the conversation seems to mimick my own style some what - in a slightly OTT way. For example Chat GPT wil now often call me "mate" or reply often with terms like "Yes mate!".

This is not far off how my own close friends might talk to me, it definitely feels like it's adapted to my own conversational style.