Thanks Saab. My wireless connection via the MBP is completely dead. So, I plug in an ethernet cable to access the net. However, via this cable, I can see other wireless devices that are connected to the router.
Here's something really interesting:
Apple - Support - Discussions - Dropping Wi FI Signal ...
A few people are having my problem. Ever since I upgraded to SL, weird stuff happens like losing effects on iPhoto slide shows and so on. I made a post a few months ago on this thread and love showing it to the Apple 'genius' folks in Apple shops that I visit.
Back to the problem, I now put on a pw on the router, everything that used to connect to it won't until I enter that password on ea of the devices, ie the Powerbook, a Vista machine and the iPhones. The MBP wireless remains dead as a dodo.
All points to a problem with Apple's AIRPORT upgrade with SL.
No one else knows how to change the router as I am the de facto tech "expert".
Any ideas? I keep defending and loving Apple products but am beginning to look silly with these SL bugs! Thanks for your help.