Does anybody know if there are any implications of going for citizenship if your partner is working abroad whilst the family is based in Australia?

Citizenship eligibility is based on the applicants residence in Australia as a PR. The applicants family's residence is irrelevant. Your partner must gain the 2 years in 5 residence with 1 of the years being in the previous 2 to eligible for citizenship.

If you are applying within the country, on the forms there is a bit about being in the country for your interview and the ceremony.. if you have to leave the country , to work etc for a period of time, you must inform of them of the dates you will be away from Aus . To get citizenship here you have to have an interview.. this can be re- arranged at a date to suit you. When you pass the interview ( I'll say when and not if) .. you are then sent a ceremony date, which you must attend to swear an oath and collect your certificate.

here's the link for applying for citizenship if you want to read through it, and download the forms http://www.citizenship.gov.au/

If you can't find the answers you want, there are contact (phone numbers etc) details for further information
Phone the Citizenship Information Line on 131 880

you can submit your application online ( which I did) .. it's quite easy.