We are REALLY not ready for 1.5 yet.
I do hope we'll hear soon on a date for the next beta patch, 1.4.1.2. There are still major bugs being found in 1.4.1.1 and some of them QA has only logged in the last 48 hours. Some of these are huge - disappearing colonies on load; entire nations getting annexed when they only ceded one province; AI not annexing its vassals; coalitions sometimes lasting forever with the AI not leaving at +200 relations; and more.
Also, 1.4.1.1 beta was missing a couple of important feature changes that PDS developers had said were coded, but which did not make the 1.4.1.1 release. For example, the ability to sell any of your cores to a subject who then gets a core on it (transferring your core to them.)
We need a second beta, 1.4.1.2, both to re-test the significant new bugs found and to test for the first time those 1.5 features we've not yet seen.
I am hoping that 1.5 is at least two weeks away, maybe three - so that we have a 1.4.1.2 beta next week for at least a week, maybe two, then 1.5 hits.
I realise that that would be frustrating for some who want to play Ironman and MP. But remember that while we are in beta, there is a chance of issues being fixed and changed. Once 1.5 hits we will at most get one or two hotfixes that will only resolve a few major bugs, and probably not all of them, and not make any feature changes. After that, we'll have to wait maybe two months for 1.6.
It's better to wait a couple of weeks to get a 1.5 that's working really well, than encourage PDS to get it out soon and maybe live with major issues for months. The reason you can't currently play Ironman reliably in 1.4 is because of bugs like that - it would be terrible if that persisted into 1.5.