They run through each series sequentially, but you do have to switch them after each block (of 5, 6, 10, 12, 20 videos, etc.) You can also switch videos after a couple of seconds (watch for the video number to change to a check mark) to get through faster. They really just want you to get through the ad so they get paid.
Do you have search results as your homepage, or just swagbucks? Needs to be your search results, here's a video on how to change your defaults -
https://www.youtube.com/watch?v=s3jwYVLYYzk
You can also get alerts from sc-s.com whenever a new swagcode is released.
Also check out the peanut labs surveys. I find I qualify for more of those than the gold ones and you also get 1 sb if you get disqualified.
You can also print your smartsource coupons from swagbucks and get 1sb for each coupon redeemed.
Typically each week there is a different contest of some sort that you can earn bonus points with.
You can also download the swagbucks video and tv apps and earn for watching videos. These videos typically stream seamlessly, but everyone once and a while you get an add that you have to close a window on.
Unfortunately, it's not a totally passive program.
Good luck :)