64 years old, and I NEVER heard 'tickety-boo' before...and I cannot comprehend why it would have been adopted by myriads of people as a useful expression. Some slang/vernacular/euphemism is 'quaint'...and some is clever and pertinant...and some is just plain silly and stilted.

(humorless, grumpy old curmudgeon, am I?...*grin*...you betcha!)