The machine packs in a 1.33GHz processor and is (obviously) slightly heavier (1.2kg) due to the lovely big 12in WXGA (1,366 x 768 pixel) display.
The machine is also slightly wider than those Inspirons Dell has already officially announced at a 29.9cm (11.8in) dimension, with a 40GB hard drive running Ubuntu Linux.
"We knew Dell had been toying with the idea of a 12in subnotebook for some time but they have yet to make an official statement. The fact Tesco has posted it on their site regardless, shows the growing strength of the supermarkets in the low-end IT market," said Michael Browne, editor of What Laptop magazine.
"Of the Web Browser itself, as Tesco is calling the device; the use of the slower Atom Z530 chip is something of a surprise on what is frankly a larger machine."
Brown adds: "Good to see that Ubuntu will also be making an appearance but I'd be sceptical about the overall weight being 1.2kg, as this may well be without the battery."