This study sheds new light on the under-investigated Weak Vowel Merger (WVM) in Australian English whereby an historical contrast between unstressed KIT and SCHWA has been lost in favour of a central schwalike variant. We address the following questions: (a) to what extent are unstressed vowels derived historically from KIT realised with a centralised quality as per conventional accounts of WVM; (b) does the status of the lexical item as grammatical/non-grammatical impact significantly on the realisation of the unstressed syllables; (c) to what extent is any centralisation correlated with the duration of the unstressed vowels? We present acoustic analyses of the quality and duration of 2745 tokens of historical KIT by 40 speakers (20M/F) aged 18-22 from Perth recorded for c. 30 minutes engaged in an unscripted conversational interaction. While our findings are largely consistent with the conventional WVM analysis, they point to additional complexity that warrants further investigation.