The rise of the tablet is one of the biggest trends in computing today and there’s little reason to doubt that this trend won’t get anything but stronger.

The new iPad smashed sales records, affordable tablets with rich content ecosystems like the Kindle Fire are helping bring these devices to the masses, and Intel is promising a slew of new tablets when Windows 8 is released later this year.

The growth of the tablet market in both size and scope is affecting numerous markets. Perhaps one of the markets most affected: television.

According to a report from Forrester Research, tablets are driving the second screen phenomenon, with a whopping 85% of tablet owners in the United States are using their tablets while watching TV. All told, these television-watching tablet owners spend 30% of their tablet time while the TV is turned on, making the tablet, for better or worse, one of television’s best companions.

But the tablet isn’t just a television companion. For some consumers, it’s the new television. Forrester says that many tablet owners report watching more online video thanks to their devices and “are using tablets as personal TVs where they had none before: the kitchen, bathroom, and airports.”

Forrester’s Sarah Rotman Epps notes that this not only has profound impact on content producers and television/cable networks, which are increasingly developing second screen strategies, but also for any company building tablet experiences. “If your product is something else besides media — a software application, a bank account, or apparel, for example — assume that the living room is the primary place where consumers will engage with you from their tablet, and that the TV will most likely be on,” she writes.

Needless to say, the tablet’s relationship with the television creates numerous opportunities and challenges. At this point, the challenges appear in some cases to be significant, and the best opportunities may not be immediately apparent, but one thing is for sure: consumers are embracing the tablet in a big way and companies have to assume that their relationships with consumers will increasingly have to include their tablets.