R.E.M.'s significance has more or less coincided with the rise and fall of "college rock;" therefore, new releases have been met with increasing indifference with the in-crowd. Too bad, because the band has amassed some impressive post-I.R.S. records that consistently provide moments of brilliance. From the sell-out fears of Green (released-gulp-ten years ago) to 96's studio behemoth New Adventures In Hi-Fi, R.E.M. have gone out of their way not to merely rehash Reckoning (sigh), and are always interesting enough to justify their popularity. Even the ready-for-VH1 Out of Time wasn't the artistic undoing it first appeared to be. That said, Up may require the biggest leap of faith yet for longtime fans, especially those still waiting for Peter Buck to get his Rickenbacker back from the Hard Rock Cafe. Sounding a bit like the Michael Stipe Experience, Up not only replaces the retired Bill Barry with  hip drum loops and electronic noodling, but provides only glimpses of the once defining element of Buck's guitar work. Opening track "Airportman" sets an electronic lounge tone, with Stipe's understated vocals awash in mellow Eno-esque minimalism--something prevalent throughout the record. While this formula may be best left to hi-ball drinking neophites, the fact that Up doesn't fail outright is testament to the band's ability to turn what could have been mere studio eccentricities into great songs. The results are so successful that ``Daysleeper," the most R.E.M. -sounding track, seems somewhat out of place and is ultimately unmemorable. Stipe's voice is still expressive and vulnerable amidst such highly produced songs like the Leonard Cohen- sampled "Hope," "The Apologist," (sort of a "So. Central Rain" for the 90's) and the dramatic "Walk Unafraid," which should be enjoyed before radio programmers get a hold of it. Up is perhaps the oddest and most moody R.E.M. record, entrancing and engaging throughout. It's an encouraging effort from a band intent on defining itself again--even if the kids aren't emulating them anymore.