My 2 cents:
Yeah, Cofty's right in that 'agnostic' is a useless term, since the term was coined by TH Huxley in the 19th century and his inspiration was to contrast his position on the existence of God with that of the extinct gnostics (they were long-before squashed by orthodox normative Christianity, in 300-500CE). The gnostics were those early Xians who felt that knowledge (gnosis) of sprititual matters was given as a gift from God in the form of Divine Revelation, such that they claimed to simply KNOW with ABSOLUTE CERTAINTY about certain "secret" spiritual matters which Jesus only shared with the cream-of-the-crop believers, the 'in-crowd'.
(A GREAT comparison would be those who claim to hear God's voice today, those who just KNOW certain spiritual matters as TRUTHS. Us 'non-hearers' would thus be described as 'agnostics', since we apparently haven't been gifted by God or deemed as worthy to warrant bestowing with this special knowledge. As such, I suspect Huxley's term 'agnostic' required one's tongue being planted firmly-in-cheek, since such types have a tendency to come off as pious "Holier-than-Thou" personalities; they cannot help but coming off as gloating, even by only casually mentioning their 'special gift' to others).
In order to support the concept of the Divinely-inspired authors of the Bible, orthodox theologians placed this God-given knowledge on a pedestal, while dismissing those who made the claim of revelation in modern times as nut-jobs; the gnostics actually encouraged these experiences in the rank-and-file, validating such personal experience of Divine revelation by even placing it above one's conflicting a prioiri (pre-existing) beliefs. Hence why philosophers and theologians will claim that Divine knowledge is a special SUB-SET of beliefs, and is to be given greater weight.
It's completely bassackwards from the findings of psychcology and neurology, where the assumption is that ALL knowledge is simply information (both true AND false), but BELIEFS are defined as that information the individual accepts as TRUE (although they may NOT be, eg delusional beliefs). That's a more-modern view, and note that God is nowhere in the definition. Note that beliefs are a SUB-SET of knowledge, and given no special weight due to the known-phenomena of delusions (beliefs which aren't true).
So in contrast, Huxley claimed he hadn't been given this special gift of Divine knowledge from God, and hence couldn't claim he could KNOW God exists.
However, the unintended consequence is the term 'agnostic' actually validates the concept of Divine revelation from Gdd ('gnosis') which has been long-since been discarded as worthless, since it assumes that an individual can confirm the existence of God by hearing voices, AKA relying on internal validation (which is a form of circular argument): hence 'gnosis' is useless, as we know that up to 10% of individuals will experience an auditory/visual hallucation at some time in their lives. Why premise a position of not deciding on the existence of God, based on a flawed concept, an ambiguous term? The term 'atheist' is clear: it contrasts to 'theists' (those who believe God exists). Not so for 'agnostic'.
Of course, most modern people don't know that he was referring to DIVINE REVELATION (gnosis), and NOT just their position of not possessing general knowledge (AKA evidence) on which to make a rational decision, and hence the meaning of the term has changed in their minds. And good luck explaining all of this to people, since the term has taken on a different meaning and built up a momentum of popular usage (which happens frequently in language)!
That's why some are calling for discontinuing the use of the term 'agnostic', and instead using a system that is more-useful since it clarifies who bears the burden of proving their claim in a debate: this is the 'soft/hard' adjective, combined with the noun, 'atheist/theist' (eg 'hard atheist', etc).
But until everyone adopts that system (I wouldn't hold my breath!), it would be better to add 'agnostic' to the list of terms that need to be defined (eg 'God(s)', 'religion', 'theist', 'atheist', etc) BEFORE beginning any meaningful discussion on the question of God's existence, since you cannot safely assume that the other person's usage means the same as yours, and such misunderstandings result in wasted time and agro.
Adam