I know you don't rep fantasy but I was wondering whether you knew the answer to this through your colleagues and general involvement in the publishing business.
On the majority of the agent and publishing blogs and information sites, the word is that you won't get a look in with an agent or a publisher with a fantasy novel longer than about 100K words, maybe stretching to 120K at most. It's been a pretty consistent message for the last few years; query review websites will say agents won't even read pages if they see a word count greater than 120K.
The thing is, I can't remember the last time I've picked up a fantasy book that wasn't at LEAST 150K. I scanned my bookshelf and can't find more than a handful that would be close to 120K. Virtually every big name in fantasy puts out books much, much longer than that, and this is true of NEW big names too, not just established authors. And as a reader, I strongly prefer longer fantasy books, as does every other fantasy reader I know. So if no-one is getting agents or publishers with long books, where are all the skinny little fantasy novels that should be coming out?
Anyway, I wondered if my viewpoint is skewed because I do read a lot of Australian fantasy but most of the blogs are American. Do you know if the Australian publishing environment also reflects this new(ish) rule about length? And if it really is a rule, even here, do you think there's a chance it will change as ebooks take a greater market share, and length doesn't cost publishers anything?
That seemed a bit long and rambly in hindsight. Anyway, would love your viewpoint if you have the time and/or inclination!
Who says I don't rep fantasy? Maybe I just want you to think I don't rep fantasy ...
I'll start this answer near the end of your question: you read a lot of Australian fantasy but most of the blogs you read are American. Australian fantasy novels are usually as long as the story takes - I've never heard of a word limit being imposed on submissions, either by an agent or by an author. Some word counts are a bit outrageous - we don't want anything that is 500 000 words in a single volume - but most writers don't come up with such word counts anyway.
However, there is another issue with Australian fantasy: we're running out of places to publish it, at least in 'legacy' (i.e. print) mode. There are two large publishing companies who handle fantasy manuscripts - Hachette (who publish the Orbit imprint) and HarperCollins (Voyager). When the Borders and Angus & Robertson stores closed, they lost a large chunk of their fantasy booksellers. Consequently, they are not looking for as much fantasy as they used to, especially as they have existing authors who are writing trilogies or who may have new novels to bring to them soon.
What this means for Australian fantasy authors is that they may well have to submit overseas first or at least simultaneously - which means they'll come up against the word count limit, if it exists. I'm not an expert on the US market so I don't know if that limit is, in fact, real. If it is real, though, it may change - and you'll be able to thank George RR Martin for that. Those books are big. The sales of those books are big. They may change publishers' minds about big fantasy books (and yes, yes, I know, they're not 'fantasy' like some books are 'fantasy' but you can bet that publishers think they're 'fantasy' and that's all that matters when it comes to submissions).
If you wish to submit to US agents who rep fantasy, I recommend you check their submission guidelines as a first measure to see if they mention a word count limit. If they do not, you can presume that there isn't one - or, at least, an arbitrary one. That doesn't mean you can write 200 000 words just for the hell of it - your story has to work. If your story works and it takes 200 000 words to tell it, then so be it: that's as long as it takes. If an agent wants to take it on but they think publishers will say it's too long, they'll work with you to trim it down. But don't worry about it until then unless they do mention a limit.
Also: someone should start an Australian fantasy publishing house! Except for that pesky bookseller problem, there's a market there for those stories. Due to that pesky bookseller problem, however, that market is probably going to be digital from now on.