Is web based Point of sale getting a little more respect? This article on TechCrunch indicates that may be the case. Pose - an Israeli company - received $300,000 in funding recently.
A number of companies are already moving their platform to the Internet, or some, like MerchantOS and CashierLive, are exclusively Internet based point-of-sale systems. While the number of installed Internet based POS systems are relatively small compared to existing POS systems, it is a space worth watching. Among other things, a web based system eliminates the need for backing up, performing system upgrades, and is generally platform independent, running on PCs, Macs and presumably (shortly if not currently) tablets. Another advantage is that a business owner can dial in on his laptop at any time and check up on sales, inventory and margins.
Also worth reading - on www.pointofsale.com - MerchantOS Demystifies Web-Based POS Software