The Eclipse Development Process leaves only one week of formal review for an official release. Theoretically, it is during this time that a member company could object to the release that, for example, they believe infringes on their intellectual property. This has never actually happened in my tenure.
One week is far too short a period of time to engage in any sort of comprehensive review. But this works because it's all done in open source. Any individual or member who feels that there is some show-stopper issue with a project may interject at any time. Eclipse open source projects are required to operate in an open and transparent manner so all committers have equal power. Further, any sort of last minute dump of content would invoke the IP Due Diligence process, which mitigates the risk of that happening. Frankly, if a member company cares about the activity of a particular open source project, they can jump in and join the conversation at any point.
In short, if you're complaining during the review, you've waited too long.
I will point out that I have mitigated shenanigans in the implementation of "open" in the past. In the case where a project is not operating in a vendor neutral manner, or is otherwise skewing the level playing field, it should be brought to the project leadership chain and escalated as high as necessary.
An interested organization can literally engage with the project for as long a period as they'd like. Any company that risks lock-in of their intellectual property has committers on the actual project. That is, they would have already committed resources to that project that have equal power to effect change and generally keep an eye on the state of things for their corporate masters.
FWIW, I completely understand that there is a difference between reviewing locked-down content and reviewing a moving target while a project team works.
Wayne