I'm just throwing this thought out there for consideration, I have no information outside of our random speculation and I am fully prepared to be proven 100% wrong on this...
As reported earlier, Apple bought the domain "iSlate.com" in 2007 as well as a registering iSlate domains in a bunch of European countries throughout 2006. That, combined with the New York Times mentioning earlier this year of the term "slate" in their preparation of the Apple tablet seems to put the chances of an Apple tablet to be named "iSlate" pretty high.
And it's not just that I am not a fan of the name "iSlate" and the IsLate or ISoLATE connotations.. I'm looking at the timing of these registrations as interesting as they were taking place right before the launch of the iPhone.
As a refresher, Apple doesn't own the iPhone trademark. They have an agreement with Cisco to distribute products under Cisco's trademark. Cisco at the time, wrote this about the issue:
Cisco owns the iPhone trademark. We have since 2000, when we bought a company called Infogear Technology, which had developed a product that combined web access and telephone. Infogears registrations for the mark date to 1996, before iMacs and iPods were even glimmers in Apples eye. We shipped and/or supported that iPhone product for years. We have been shipping new, updated iPhone products since last spring, and had a formal launch late last year. Apple knows this; they approached us about the iPhone trademark as far back as 2001, and have approached us several times over the past year.
Apple and Cisco eventually came to an agreement on the trademark but Apple would have had some contingency plans in place should Cisco have wanted too much for the name.
Think Rendezvous --> Bonjour or Mighty Mouse --> Magic Mouse for examples of Apple changing product names rather than paying the price the owners were asking for the name.
'iSlate' could have been Apple's plan B name for iPhone. The timing is right. The circumstances were right as well. If Cisco didn't budge on the iPhone trademark, Apple could have switched the product to iSlate with Apple's new registrations.
Well, that's just something to consider. I don't really like the 'iSlate' name for a tablet product. But that doesn't mean it won't happen. I didn't like 'MacBook' as a replacement for Powerbook or Airport "EXTREME" either but it seems to have done Apple well enough.