Om Malik sums up some of the issues surrounding Web 2.0 and the enterprise well in a piece called The Myth, Reality & Future of Web 2.0
The Web 2.0 apps leverage cheap hardware, open standards and availability of plentiful bandwidth. Inside the firewall, bandwidth is many times what we have on the public Internet. Cheap hardware and open standards are pretty much a given in any enterprise. But more importantly, the size of the audience is predetermined, and the operating environment is more controlled. This eliminates some of the issues of scale and scalability associated with consumer-facing applications.
And frankly, most enterprise applications could use a serious makeover.
[He’s links to some great articles and there’s an interesting discussion off the back of it, so it’s worth a read in full].