From today’s release notes:

Claude in Xcode is now available in the Intelligence settings panel, allowing users to seamlessly add their existing paid Claude account to Xcode and start using Claude Sonnet 4. (155826755)

When using ChatGPT in Xcode, users can now start a new conversation with either GPT-4.1 or GPT-5, with GPT-5 set as the default. (158342780)

I’m not sure how useful developers will find the updated ChatGPT integration, but I believe Claude will be very popular among a specific sect.