Hi Geoff, I dont think we'll be having anything comparable for some time mate, unfortunately! you never know tho, there has been years in history were there have been two or 3! great comets in one year. you only have to look back at Hyakutake in 1996 (best for northerners for longer - circumpolar it was!! like a big clock hand!- we did get the tail pointing south west or west, so it was over our heads for a few days
) and then they got hale-bopp the following year! which hung around for months at a very decent object status, but there has been in history (maybe for only one hemisphere from memory, dont quote me on this tho - and i aint googling to get it right dammit ehehe) a 40 year period without a great comet! so who knows?
best future planner is this page, to my mind, from Seiichi Yoshida
http://www.aerith.net/comet/future-n.html