I hear Epson is going to announce early but make take quite a while (as they always do) to get printers to market. Epson is the smallest of these three companies and has the slowest to market capabilities.
I thought Epson did well with shipping the last printers from announcement to delivery. The 3800 made it to market in record time, and was pretty much trouble free. OF course the 24" and 44" are much more time consuming on assembly thus a longer time required for getting to channels would be acceptable anyway.
If the notions of larger gamut are true , and there is that extra print head channel waiting, will it be the best solution to have Glop over a primary?
Where the HP really sings is in printing landscapes with Fuji type of greens that the current Epson cannot print. As you said Epson must be looking to catch up in the few outstanding points that Canon and HP are stronger in , and this is a big one.