NEW YORK (CNNMoney.com) - A late-stage dose of heavy discounting appeared to be exactly what the doctor ordered to rev up crucial December sales, as apparel sellers, high-end merchants and even one long-time laggard in the home furnishing arena posted surprisingly strong numbers.

Teen clothier Aeropostale (Research) and American Eagle Outfitters (Research) both reported sales at their stores open at least a year -- a key retail measure known as same-store sales -- that soundly trumped Wall Street's forecasts.

Aeropostale's December sales rose a solid 11.4 percent, while American Eagle's climbed 9.8%. Analysts had forecast sales to rise 4.3 percent at Aeropostale and 3.5 percent at American Eagle.

And sales at Abercrombie & Fitch (Research) jumped 29 percent. Based on its year-to-date results, the company said it was increasing its profit forecast for its fiscal year ending in January 2006 to between $3.58 to $3.63 per share. Excluding a one-time charge, the retailer expects earnings of between $3.67 to $3.72 per share.

The one glitch in Abercrombie's mostly positive story was disclosure from the company that the Securities and Exchange Commission is formally investigating trades involving its shares. The retailer had previously been the subject of an informal SEC inquiry into the matter.

Abercrombie said the SEC has requested more information from both the company as well as from some current and former officers and directors. It said it was cooperating fully with the agency.

Within the universe of 68 retailers tracked by First Call, 59 percent beat their December same-store sales expectations, 39 percent missed and the remaining two percent met.

Ken Perkins, retail analyst and president of research firm RetailMetrics, said he was not only impressed by the sales numbers, he was scratching his head over how these companies also managed to deliver some very good profit news.

Aeropostale was extremely aggressive with promotions during the holiday season, and that raised concerns that an increase in sales might sacrifice margins.

But that wasn't the case. The company actually upped its fourth-quarter net estimate to between 71 cents and 73 cents a share from its previous forecast of 55 cents to 61 cents a share.

Said Perkins, "Aeropostale must've built the steep discounts into its holiday margins. To raise its expectations by that much is very surprising. I think its the biggest surprise of the season so far."

American Eagle, which was also very promotional in the key November-December gift-buying months, said it was maintaining its fourth-quarter profit outlook.

Other names on the winners' docket included teen apparel retailer Wet Seal (Research), which saw same-store sales soar 38.5 percent last month.

In the women's apparel arena, Chico's (Research) posted a 16.4 percent same-store sales gain in December. Limited Brands (Research), parent of Victoria's Secret and Bath & Body Works chains, saw sales increase three percent.

Men's clothing was another bright spot. Men's Warehouse (Research) saw its sales increase 8.1 percent.

In home furnishings, Pier 1 Imports (Research) surprised Wall Street for the second month in a row with numbers that were a little stronger than expected. The retailer's same-store sales fell by 4.8 percent, better than analysts' expectations for a 5.1 percent decline.

Deutsche Bank analyst Michael Baker said Pier 1 should benefit from easy sales comparisons in the months ahead, but that the retailer's not our of the woods yet.

"Based on today's release and our numerous store visits during the month, it is clear that despite some positive product recognition and conversion resulting from Pier 1's catalogs, heavy promotions are still needed to drive traffic," Baker wrote in a research note to clients. "We saw sales of 50 percent [off] during almost all of the month, including up to this past weekend."

J.C. Penney (Research) was the standout in the department store segment, logging a 2.2 percent sales increase last month.

Not everyone made it to the party.

Sears Holding (Research), parent of Sears and Kmart, reported that sales at the Sears (Research) division slumped 11.9 percent, while store sales at Kmart rose a meager 1 percent.

Same-store sales at leading apparel seller Gap Inc. (Research) fell a steep nine percent. Industry watchers faulted the retailer for its merchandise mix, which failed to excite consumers for most of last year.

However, Gap stood by its year-end profit estimate of between $1.12 to $1.17 a share, adding that the numbers were trending to the upper-end of the range.

Wal-Mart (Research) didn't have much to smile about after it reported that fourth-quarter profit would likely be at the low-end of its forecast, citing a disappointing December.

The world's biggest retailer saw same-store sales last month rise just 2.2 percent at its U.S. stores open at least a year, and said it expects profits to come in near the low-end of its forecast of 82 cents to 86 cents per share.

Wal-Mart's lackluster performance last month was a bit unexpected, Perkins said, given that the retailer's aggressive start to the holidays that helped spur November sales up a respectable 4.3 percent.

"It could've been one or a combination of three things that hurt them," Perkins said. "Wal-Mart ran out of the Black Friday doorbuster items that pulled shoppers into its stores after Thanksgiving. Their holiday advertising and marketing was weaker later in the season. And you also can't discount the fact that low income consumers who've been feeling the pinch of gas prices and higher energy costs were more cautious with their spending."

Wal-Mart rival Target fared much better. Target (Research)'s December sales rose 4.7 percent, beating analysts forecasts for 4.6 percent gain.

"You have to remember that low-income consumers really took a hit in 2005," said Marshal Cohen, chief retail analyst with market research firm NPD Group. "A lot of them maxed out their credit cards at the beginning of the season and then got their winter energy bills. That probably left them with an absence of cash and discretionary spending later on."

Looking to January, Cohen said gift cards and more markdowns could help pump up post-holiday sales for those retailers who had a "yucky" December.

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Retailers are already selling spring clothes in January to try to boost gift card-driven post-holiday profits. Click here for more.