that pic above is very good for a controlled concert pic. little front focus on the drums (no surprise as AF was probably used and the high contract auto focus point selected was the bass drum) though.
IF that is the minimum quality you're looking for keep reading and we'll talk digital SLR cameras.
along with what Rotti and others said let me add this...
Indoor concert/event you'll need to use iso1600 (iso3200 is better) and apply a noisemonkey or equivalent filters as needed. Sample shots and the histogram will show light metering and if you need iso3200 use that. It's easier to remove NOISE than it is to add light to a photo
ALWAYS shoot in RAW format which allows post-processing exposure adjustments without introducing JPG and other artifacts and picture glitches.
For concerts i've used SLR 35mm film, compact digital and a dSLR (canon 10D). the compact digital (pre affordable dSLRs) was too slow in regard to shutter lag and everything else. The 35mm film SLR worked best (no surprise) but i attribute some of that to user error (the 10D was new) but more importantly to the fact the same lens on a film SLR was inaequate on my dSLR. This brings me to the next point...
Lens selection is crucial... wrong lens on great body will get you bad results. i would NOT recommend even a 2.8 lens unless you were stuck requiring a long zoom. even then i'd try for a f/2.0 prime lens cause you NEED light to get good pics and flash is useless from a distance (and up close really).
Assuming new 8-10 megapixel dSLR you get better results using a shorter lens with proper exposure and cropped, as opposed to a "perfect zoom" picture with poor exposure (ie. slow zoom lens). Refurb Rebel XT is $400, i'm sure you can find better deals if you look (XT or XTi)
For concerts I would go with a FAST prime lens. Canon 50/f1.4 (or sub $100 as Rotti said f1.
or Canon 85/f1.8. the 85 is a fast focus lens and good performer... lets ALOT more light in than f2.8. careful though as shallow DOF requires good focus
so if Rotti had the f/1.4 lens he could use an appropriate shutter speed and when the drummer was playing or other band member moving around there would be not motion blur (from slow shutter required to let enough light in).
i think motion blur adds a cool effect to some pics but i'm assuming the goal is sharp, crisp pics in a dark concert and you need FAST FAST FAST lenses and a dSRL minimum level of Rebel XT. I would pass the cheapie nikons which have a sony CCD sensor which has alot of noise above iso400... horrendous for low light. even the d200 will suffer at high ISO. Canon wins there hands down and is why i'd recommend them for almost any dSLR buyer starting from scratch with no lenses... glen