@Suneshine It's a sales tactic and to be honest, I really don't care if the TSV is announced a week early or the day of. I rarely buy TSV's since I rely heavily on reviews and generally, TSV's are new and have no reviews.
With that said, I do purchase many food items that are TSV if like or similar products have reviews. I have never missed out on anything that I had to have.
I live on the West Coast. By 9:00 PM I am usually done on my computer so I wait until morning to check out what QVC has as the TSV and Lunchtime Specials. This would be about 9:00 AM eastern time and I have never missed out on anything.
Like another poster said, most of us live busy lives. It just takes seconds of your day to check what the TSV is if you are truly interested. No biggie for me, but I do feel there is more anticipation and perhaps more impulse buying if you know there are only hours left. If it isn't financially productive for QVC then they will go back to pre-purchasing otherwise, if it stays as is then it must work for them.