If you want to go viral on the web, keep in mind that the old rules no longer apply. In the past, when someone did something to attract public attention, such as sending a balloon over a city, or any other type of "publicity stunt", it was important to make it clear what it was for. If people couldn't figure out that you were, for example, promoting a new housing subdivision, it just annoyed them. When people found out that the balloon was for John F. Long Homes, then they felt a whole lot better. But on the web it's different.
Doing a blog or a video, or anything for that matter, that is obviously selling something on the web is more like putting a flyer on someone's windshield in a parking lot. People may glance at it, but chances are they aren't going to go put it on all their friends' windshields. So, to give your meme a chance to go viral, it's vitally important that it have no selling point.
Also, consider how important a title is. Fred's Blog About Stuff isn't really going to attract attention. If you want to know what kind of titles attract attention, go look through the list on Digg. You will see what I mean. Boring titles equals no click. On the other hand, if you flat out lie about your meme, then when people get there, they will feel cheated, and they certainly won't share it with their friends.
If you are writing a blog or uploading videos to promote your business, don't worry about going viral. Chances are very good that you won't. But this is a different goal. If you are in business, give your customers the information they need, and make it easy for them to purchase your product or service. You may not get a million hits, the ones you do get will matter.