Personally I waited since 2012 when I found out about SG and made this forum account, so I don't mind waiting more, the problems arise when promises are made and not followed, and so far, the latest update came out 10th of November, and the latest ETA that's been given states as soon as possible (ASAP) so you can be sure it will come as soon as Madoc and the team are done, it doesn't state a specific date, but they have said, regarding the latest update, that Its been far too late to be released (It took them 4 full months I believe), so you can certainly infer from this that it won't take 4 months anymore.
So far, It's been less than a month, so it would be safe to assume somewhere around 2 months, January, which is very incredible rate of progress compared to the sheer size of updates they put out with the amount of content they have, the arena update is going to be amazing I'm sure, Madoc and the team are simply perfectionists, they try to limit that so the updates are released on time, but you're getting fairly big chunks of updates which are usually very complete and bug free due to how closely the team works with the insiders, I believe BM is doing a better job at communicating and staying transparent now than they have in the past, and personally I am thoroughly impressed and my "Thirst" for any kinds of update is non-existent, I can safely rely on the team to give periodical teasers and updates now and then, I suggest checking the Exanima steam forum discussions and viewing posts from BareMettle (The steam account), also, checking "What's new" on the forums is a fairly safe bet to get new information every now and then, though the steam forums are better as most of the public is there and never even finds this forum, and the forums are more of our own personal discussion hub.
In case you've missed it -
https://steamcommunity.com/app/362490/discussions/0/492379159717217907/
They've posted an update 1st of Dec, 4 days ago, not much is going to change in 4 days, so this *should* satisfy anybody who's hype cannot be contained anymore, hopefully, it did yours.