hi @Samuel_Langford , to my understanding we will have 3 types of tables
simple tables (grid)
standard tables (we have today)
power tables (up to 1M rows)
the power tables will live on workspace level and can be brought into your docs, eventually linked to permissions on row & column level and as such offer a faster and more reliable alternative for cross docs due to larger data sets and instant modifications.
I expect an update this spring from @Nathan_Penner on it when a (closed) beta will be launched. Make sure to be part of it 
Cheers, C
Christiaan