From what I have been able to determine here in Texas....it's stacks on stacks on stacks...There are already so many exits on most freeways anyway, and with our frontage road system, a large number of them are slip ramps onto the frontage road, with an onramp either just before or just after the intersection.
I am seeing quite a few braided ramps used in some places, especially where there is heavy development.
But for the most part, when there is a new interchange, or an interchange is being redone, it is some form of stack...whether its the huge sprawling 5-levels at major freeway-freeway junctions, or just a couple of direct connectors.
At least in my part of the state, Houston, there are almost 0 cloverleaves...the the only interchanges even really resembling those are at frontage road to cross street intersections...and those are rare...there is one on Memorial Drive...and Beltway 8 has a cloverleaf interchange with Westpark Tollway....San Antonio and Dallas I know have several, though.
But here, most of the new ones are stacks...or they are converting non-stacks in to stacks... like Beltway 8 and 225, Grand Parkway and SH 249; or redoing old ones like IH 69/US 59 at IH 610 or the big rebuild they did near downtown for IH. 69 and IH 45