@gchak arXiv has an RSS feed for each of their categories. I just point my script at the feed, parse the results and then go through the papers.
The RSS feed generally updates only once a day — about two hours ago from now. So you don't really have to worry about new papers popping up through the day 🙂
The feed for cs.CV is here:
http://arxiv.org/rss/cs.CVYou just have to change the last bit for the category you want ...