Valentine's Day E-Cards Bring Great Expectations . / Credit: Unicorns Valentine image via Shutterstock

More than a third of Americans will let e-cards serve as Cupid's messenger this Valentine's Day. And most of us will expect something in return, a new survey shows. But somewhat surprisingly, e-card senders were not over the top in their quid pro quo expectations, according to a survey of more than 2,400 U.S. adults commissioned by SOASTA, a cloud and mobile testing company. 

While a majority (54 percent) said they expected something in return for sending an e-card to a romantic partner or love interest, more than a third (35 percent) said they would be happy with a simple "thank you."

Only a slim minority expected a major reciprocation that involved either dinner (10 percent) or sex (10 percent).

Married Americans say their spouse is the No. 1 person to whom they plan on sending an e-card (28 percent). That was followed by American adults who said they’d send one to friends (14 percent), parents who would send one to their children (11 percent), American adults who’d send one to their mothers (9 percent), boyfriends/girlfriends (8 percent), fathers (3 percent), grandparents (3 percent), secret crushes (3 percent), employed adults who’d send one to co-workers (3 percent), the attractive receptionist at work (3 percent) and bosses (2 percent). 

The popularity of e-cards is pretty easy to understand, the SOASTA survey shows. Nearly three out of four (73 percent) respondents like something about e-cards — the fact that most are free tops

 the list of virtues (53 percent). That zero price point is followed closely (43 percent) by the way e-cards can save the day if you forget to buy a physical card in time.

Other attractive features of e-cards include animations (35 percent), being friendly to the environment (34 percent), interactivity (24 percent) and not needing to know the recipient's physical postal address.

But please lay off on the aggressively cute, the survey recommends. Recipients of e-cards don't want to see unicorns (25 percent) your kids (24 percent) pictures of your spouse (23 percent) and kittens (19 percent).

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