depending on these buys success, anything is "possible"
its really in everyones hands as to how justifiable things are in the future
i'll probably buy one of the first sets just to support the effort (very nice job with the quality and the pricing), but i agree in that some mx-to-topre compatible spacebars would be a real plus for the future. you'd be able to enter your own market space there as well, as now the only accessible replacement option is the black spacebar. every other color currently requires the purchase of an additional set/keyboard once the spacebar starts to develop shine, which is a real terrible position to be put in for topre owners.
i am curious though, do you know if topre/cm has a patent on the mx-style slider? i didn't see anything on the usa patent page, but with ya'll pricing the sliders so aggressively, you're actually likely to hurt cm's novatouch business. and i know they paid for a part of the tooling at topre's plant for them, so with all that money invested they'd be very likely to protect their patent, should they hold one.