All these speculations about BMW upping the power output on the 3.0 liter engine because of competition...Some say 260 HP on the 330 in 2003, I've seen figures ranging from 230 to 250.
The 3.0 liter engine, at current iteration (M54), is about as finely tuned as an engine of this size can POSSIBLY get at 6,500 rpm redline (without introduction of new technology). The ONLY way BMW can increase the power output of the 3.0 liter engine is by either force induction (hence the bi-turbo on the 5 series) or by moving the redline up another few thousand RPMs, ala M3 engine. Frankly, I don't think the Aluminium block in the 3.0 can sustain such high RPMs, otherwise BMW wouldn't have use a cast IRON block for the M3 engine.
And judging from the fact that the new Z4s are coming with the identical 3.0 and 2.5 liter engine, we can safely assume the 2003 3 series will NOT see any powergains, and if the numbers are different we can be assured that it's BMW Marketing working their funny accounting. Most likely we WILL see some new engines by the end of 2003 on the 3 series once the 5 series is introduced...Perhaps Valvetronic I-6es with power in the 250hp range from the 3.0, but it will NOT happen in the 2003 model year.
So take it for what it's worth, there will be NO changes for 2003 for the sedan, and very minor changes on the coupe if any.