The language is a bit different, but is the conferred authority?

regarding the school funding bill now in conference committee

Now that both the House and the Senate have passed versions of the Student Opportunity Act, it goes to conference committee, which began meeting Friday, to create a single version of the bill on which both chambers can agree.
We keep being told the hang-up is "accountability." As I said earlier this week, though, what we're talking about isn't actually some version of what we've called "accountability" in education under No Child Left Behind or the 1993 Education Reform Act. This isn't about student outcomes (of whatever merit).
It's about districts submitting spending plans, and the degree of authority the Commissioner has over that.
That isn't accountability in any way in which the term has been used in education.
What it is, of course, is an expansion of the Commissioner's authority right into the realm of the school committee. Allocation authority within the bottom line established by the municipality or -ities is under the purview of the school committee (per a 1993 Department of Revenue decision, in fact).
I haven't heard anyone talk about that.

What I have heard a lot about is this major difference between the two bills over the Commissioner's authority; see, for example, Commonwealth Magazine from earlier this week. I've heard it summarized as a question of if the Commissioner has veto power over district spending decisions. The summary has been that the House gives him that power, while the Senate did not.

I don't see that much of a difference, looking at the language of the two bills.

The language in question lies in Section 1S, subsection d.
The House says this:

Upon receipt of a district plan, the commissioner shall review the plan to ensure that it sets forth clear and achieveable goals and measurable standards for student improvement that comply with the requirements of this section, provided, however, that the district shall amend any plan deemed not in compliance.

The Senate says:

 Upon receipt of a district plan, the commissioner may recommend plan amendments that ensure the plan sets forth clear and achievable goals and measurable standards for student improvement that comply with the requirements of this section.

The contrast thus is the in "shall amend" versus "may recommend." But look at the verb that the Commissioner is charged with: in both cases, he is to "ensure" that the plans meet particular parameters.
How is he to do that if he isn't efffectively given veto power?

Commissioner Riley has said that he would love such an oversight role.