The NDP have introduced a large number of amendments to Bill C-9 (An Act to implement certain provisions of the budget tabled in Parliament on March 4, 2010 and other measures), mostly to remove the many “other measures” unrelated to the budget which have been tagged on to the bill.
If any of these amendments are approved, and the amended budget implementation bill is passed, would this still be considered as a non-confidence vote in the same way as if the complete bill was voted down?
If Stephen Harper felt like engineering an election, or were just being his usual petulant self, no doubt he’d regard it that way.
I imagine there’s a gradation; I mean, if the opposition were to successfully pass a motion to reduce all the figures in the budget to $0, that would have the same effect as denying supply. On the extreme end, deleting any “other matters” that are not, in themselves, matters of supply, I don’t think can be construed as denying supply, any more than amending a bill on any non-supply subject.
I can’t really see him wanting the government to fall just before he hosts the G-8 and G-20 shmoozefests. I doubt the Liberals have the courage to call his bluff, though, the NDP seem to be the only ones showing any backbone here. 
The Liberals and NDP cannot by themselves defeat or amend the bill. But if the Parti Quebecois went along, they could.
The PQ seem to be supporting the NDP in the debates, and a few Liberals are also speaking against the bill, but where the Conservatives and NDP are showing up en masse for the actual votes, the BQ isn’t making the same effort, and the Liberals seem to be largely missing in action.
The question is moot, now, as the amendments were voted on yesterday, and the few Liberals who bothered to show up voted with the Conservatives to defeat them.