I don't think it's plausible for ToM to have "coincidentally" made identical style choices to Fab, they're just too alike to not be intentional copying.
A generic tag icon next to the item price, in a different color? A "sale ending" notice with different color, location, and font?
To me it is absolutely certain that ToM made a concious effort to copy the style of Fab, through the composition and presentation of individual elements and the layout of the site.
Branding is very important and can very easily confuse consumers, maybe Fab are being overzealous and should have just asked ToM to stop copying their branding, but to claim that because lots of websites have clock graphics next to their timers that this isn't a copy is silly.
Whether or not they will win in court is irrelevant, what matters is that what Fab.com is claiming (ToM copied them) is (in my opinion) an accurate claim.
Their lawyers know that they most likely aren't going to win this--they're just trying to force them to pay legal costs they can't afford.
In essence they are pursing a fairly frivolous lawsuit for the sole purpose of removing competition.
37signals should start suing all the SaaS websites that were inspired by Basecamp.
A quick google shows that in fact this is sarcastic.
To win a suit for trade dress infringement it's not enough to prove the designs share similarity. The plaintiff's design must be truly distinctive and closely associated with the site.
I don't see anything distinctive about Fab.com's site, it looks exactly like dozens of other e-commerce sites. Furthermore no one is going to look at a product page with a picture on the left some, a white background and grey helvectica and think--Fab.com.
They're not going to win this one.
I read the article and felt empathy for a Touch of Modern, but then I see that example and think the article is dishonest.