I mention that i am designing a language. The plan was always to not implement it but to design it but i am considering implementing it if i think i could do it in a reasonable amount of time.
How would i have my language use intellisense in visual studios? BooLangStudio has it http://www.codinginstinct.com/2008/05/boo-in-visual-studio.html, http://www.codeplex.com/BooLangStudio
This is a good place to look for Visual Studio Extensibility.
Also, here. But, the first link has a video specific to adding Intellisense to your language service.