In an effort to boost holiday sales Dell (DELL) won't launch its new digital music player before Christmas.But the company has released 2 consumer notebooks the best-selling segment of the consumer market. Still Dell lags behind its rivals.Since September rival Hewlett-Packard (HPQ) has released a pair of entertainment-focused laptops an inexpensive mini-notebook billed as a "netbook " and a notebook computer designed for Best Buy (BBY) stores.Dell hopes to increase market share by offering stylish laptops including models that come in red blue "quartz pink" and mica-brushed metal. It also released a larger high-end version of an all-in-one desktop. ...