Although my webOS version is 2.1.0, I am having a similar issue.
My recently purchased new Pre2 on Verizon (bought on 6/30/12 Daily Steals) has had a couple of instances where it can't connect to wifi. And now since last night it can't at all. If I bring up the top menu (downswipe on right side top of screen) and select wifi, Turn On, i see the little spinning wheel of despair (SWOD) beside the dropdown menu row for wifi, but it just sits there. No networks ever come up. If I select Wifi Preferences and it brings up the wifi utility app, the virtual switch on the upper right says 'Off', an i can tap it to 'On', and it shows 'On', but the message below that says "Wifi is turned off" doesn't change.
I've tried Luna resets, restarts, full power down and up.. The full power down and start up seemed to do the trick, for now. I'll keep an eye on it and may post again if the problem re-appears. I have the following patches installed:
Add Date MM DD v2.1.0-2 - tk102, CRaiaSoftware
Advanced Systems Menus - App Menu (ATT/VZW) v2.1.0-230 - sconix
Battery Percent as Icon v2.1.0-11 - nesl247, Jason Robitaille, CRaiasoftware
Buttah v2.1.0-190 - WebOS Internals
Device Temperature Warnings v.2.1.0-3 - Jason Robitaille
GPS in Device Menu v2.1.0-3 - Jason Robitaille
PDF Redux v2.1.0-4 - akamil, pcworld
Save Attachments to Downloads Folder v2.1.0-39 - Jason Robitaille
Unthrottle Download Manager v2.1.0-160 - cliomark, Jason Robitaille
I just noticed, after going to sleep on the touchstone, I woke the Pre2 up and it had lost connection with my office wifi. It seemed to have some trouble finding the network at first, but I walked closer to the router (I'm about as far away as you can get in our office) and it detected the office wifi. All this may be normal behavior, because at least the 'CHOOSE A NETWORK' box and 'Searching for networks' is there...it wasn't before.