Dan's entirely correct in saying that Mega Man Battle Network sets up the real world/internet interaction as the everyday status quo. The potential of exploring the concept of artificial life is a promising one, but perhaps too grand for a small-scale effort on the Game Boy Advance. It's also no secret that Capcom has never been known for the depth of their storytelling, and as a result there's not even the pretense of delving into the subject. The possibility for an examination of "humanity" is there, but it's obvious that such a thing was not intended to be part of the story, and I didn't penalize it. Mega Man Battle Network is clearly content to stay in the shallow side of the intellectual pool (as all Mega Man games have been), but the waves it makes with its gameplay are worth noticing.
As someone who generally stays far away from handheld titles, the mechanics and unique battle system had me instantly hooked. Simple enough to grasp in two minutes but strategic enough to avoid becoming boring, the chip system works, and works well. It's somewhat reminiscent of "card" games like Lost Kingdoms or Monster Rancher Battle Cards in that the chips function exactly as a virtual deck would. Needless to say, maintaining an efficient selection of resources is key, and the element of randomness keeps you on your toes.
Besides the solid and creative mechanics, I also enjoyed the re-imagining of Mega Man himself. By reworking familiar elements from the legendary series and recasting them into a completely different form, Capcom succeeds in revitalizing a tragically overused franchise for the second time. The titles that stay closer to the original run'n'gun formula may be predictable and stale, but the offshoots spawned by the little Blue Bomber have all had serious legs. Mega Man Legends and The Misadventures Of Tron Bonne were magnificent spinoffs, and Mega Man Battle Network is yet another worthy addition to the pantheon.
In all fairness, I must admit that the game did lose some appeal when it came to level design. Taking the concept of the Internet as a vast web of informational pathways, the areas MegaMan.EXE explores are confusing and highly disorienting. More aggravating than enjoyable, the faux-3D ramps and catwalks making up the virtual world go over, under and around each other like threads in a Gordian knot. This kind of setup might make perfect sense thematically, but in practice it's not very palatable. The small amount of area viewable at one time on the GBA screen doesn't help, either. I spent more time than I care to admit traveling in circles and pointlessly draining my batteries.
Even with this mazelike unpleasantness taken into account, Mega Man Battle Network is a highly enjoyable, solid, and creative game worth getting into. Most of the titles available for Nintendo's handheld may be little more than quickie ports or half-done shovelware, but little gems like this help make the GBA (and upcoming SP) a worthwhile investment.