Before I delve into the question of does it matter, I need to define what a Vector and a Bitmap image are.
A vector image uses geometrical formulas to represent images. The other way of representing graphical images is through bit-maps in which the image is made up of a pattern of dots (note that bit-maps are often referred to as raster graphics). Programs that allow you to create and manipulate vector graphics are called draw programs and programs that manipulate bit-map images are called paint programs.
Vector graphics are more flexible than bit-maps because they can be easily re-sized. In addition, images stored as vectors look better when displayed on high resolution printers and monitors. Bit-map images look the same, regardless of the resolution of the display. Another advantage of a vector graphic is that they often require less memory than bit-maps do. Vector graphics do not need to be translated in to bit-maps until the last possible minute, after all sizes and resolutions have been specified. Bitmap graphics in essence are a more real world snapshot containing an infinite colour palette whereas vector graphics have become the norm for logo, icon and billboard flat design.
One reason it was important historically is purely down to the resolution that a bitmap could display at. That is less of an issue nowadays since technology for storage and processing allows capturing incredibly detailed images that can print up to resolutions that don’t lose detail. Blurring the lines is the ability to convert bitmaps into vector where necessary. Although this can be a timely process and the conversions themselves there can be some glaringly obvious changes to the original piece.
So, does it matter? In my opinion, kind of. Firstly it’s important to understand will there be any further work required on the piece. If there is then it can make a world of difference. Converting round bitmap objects to vector can be quite noticeable as the anti-aliasing tries to blend itself naturally, but a vector circle looks really out of place in the real world. Blending the two modes to make a seamless image doesn’t really work but understanding the strengths of both really does. Vector boxes put on top of a detailed image has been done well as long as print has existed, long before computers.
In a sense, looking at vector and bitmap the question crops up about graphic design and does it matter. The answer to that is a resounding yes; of course it matters as it fundamentally makes the piece amateur or professional. This is where you will have people take it seriously or not.
So, to answer vector and bitmap, it very much matters but it’s the artist at the end of it that will make it fail or succeed in delivering the message.