With a substantial hardware lineup already deployed, Acer is well-equipped to offer cheap hardware in general. With this renewed approach, it'll hopefully benefit end-users by bringing a lot of very low-cost laptops to the market next year. If HP and Acer are both planning to target the low-cost market, you can assume a lot of other vendors will follow as well.
Acer's intentions to drop pricing may help them do more than just compete with HP. It may also further a related goal Acer has set for themselves, hoping to ship over 40 million notebooks next year. Becoming the number one vendor worldwide would have other benefits as well, such as giving them substantial leverage with suppliers, shipping companies and retailers -- impressive for a company that was a fairly small player in the notebook market a few years back.
Customers aren't all about price, though. Form and function are important, especially with the sheer amount of notebook manufacturers offering everything from shrunken netbooks to desktop replacements. If there's one negative aspect of price competition among vendors, it's disappearing features. Hopefully that won't be the case, and the lower prices in store won't come at the cost of useful functionality.