Its limitations are those of the physical universe: it won't let you play with some really wild ideas that aren't possible, but are fun to speculate about.

As for sticking strictly to presently known science, I will simply point out that we have already experienced at least two major revolutions in science in this century alone.

Ideally, I'd like every issue to include a diverse group of stories that meet the qualifications sketched above, but covering a wide range of specific matter and flavour.

I think the rising and falling popularity of areas like hard SF and far-future SF is, to a considerable extent, the same as any other fashion.

There may be something to the suggestion about the pace of technological change intimidating writers, though - it's been awfully hard to keep ahead of real developments.

When something hasn't been around much for a while, and one example of it turns up and catches people's eyes, they go looking for more like it - until they get tired of it again.

Don't mistake a good setup for a satisfying conclusion - many beginning writers end their stories when the real story is just ready to begin.