I run a computer lab at the University of Washington. There's a few reasons why computer labs won't go away soon for us:
1) Expensive software - if we did away with labs students would have to buy software such as SPSS, and they would need it only for a few classes. We don't think its reasonable to expect students to incur this added expense.
2) Specialized hardware - Our video editing suites will always require video editing hardware and DVD/Blu-Ray readers and burners, and having nice scanners and color printing is an added incentive to come in to the lab.
We do make allowances for students with laptops though. I've made spaces for laptops where I've added power strips and networking points for those that don't use the 802 network. We're also looking at adding groupware to our lab to make it easier for groups to work and collaborate.
We also run our help desk out of a lab and we'll help students with their laptop issues. We allow students to come and eat and relax in this lab too. We've found that this atmosphere encourages students to come back to a lab environment.