The battle for enterprise e-mail market share will increasingly be fought online. A lot of the showdowns we've heard about lately have been online Microsoft Exchange versus Google. Is Lotus in the game? It is if its latest customer is an indication.Panasonic signed up to use LotusLive cloud-based e-mail and collaboration for 100,000 employees, a deal that could balloon to 300,000 people on staff and at partners and suppliers. Panasonic has been on Exchange. Having seen a few whopper cloud deals for Microsoft Exchange (115,000 Glaxosmithkline employees, migrating off Lotus) and Google (30,000 city of L.A. employees), this is big for IBM.

I was talking today with David Rutchik, a partner of the outsourcing advisory firm Pace Harmon, for an upcoming article we're planning on outsourcing trends. When we turned to e-mail as a service, he noted that, until very recently, outsourced or online e-mail made a lot of sense for small businesses, but the savings weren't there for enterprises. Big businesses, with their scale, could run it more cheaply. Now, that's changing as traditional suppliers are forced to bring down their prices to be competitive. Google's price-$50 an employee a year-is one big reason.

Dan Rosenberg has a good take on this deal at Cnet--that this offers some validation for cloud among big, conservative companies, and that it furthers IBM's leadership role in the cloud. I didn't need much convincing on that first point--every big CIO I talk with is looking hard at SaaS. But what I haven't heard often is those same CIOs talking up Lotus in the cloud.

My hunch is we're going to see a steady stream of cloud e-mail deals this year. What do you think--will Lotus will be landing more big fish like this one?