From what I understand, it's the other way around: it helps creating bitmaps from vector images. Since Photoshop is bitmap oriented all vector images that were pasted were instantly converted to bitmaps - losing all the properties a vector has. With the smart-object is is sort of a hybrid solution: in Photoshop you will 'see' it as bitmap but when it is scaled, rotated etc. it 'renders' the layer using the original vector thus retaining the vector properties.
So it will not help vectorising but it will enable marquee/CP/sideart designers to create high-res bitmaps with vector based images in Photoshop.