Oh well… comic character continuity is not forever I suppose.
DC Introduces New Lobo With Latest “Villains Month” Art Tease
The writer has already come out and said that all isn’t what it seems and that the image will make sense by page four of the story.
Lobo still looks like Lobo on the cover.
The new art is whatever, but taking the character seriously?
He’s also apparently currently a member of Stormwatch (but I haven’t read that book in almost a year).
However, this isn’t eliminating the Main Man, according to the linked article, it’s a separate character, whose identity the Main Man apparently stole. So it’s a much smaller retcon than it seems just from the picture and ‘new Lobo’ headline.
This is honestly reminding me of the ‘more alien’ Superman thing.
I seem to recall that when Lobo first appeared in the pages of L.E.G.I.O.N., he looked more like a teen than the steroidal hulk he later became.
I guess I’m the only one who’s been away from comics long enough to have thought the OP title was meant to be “logo.” 
Lobo’s first appearance was in Omega Men, almost a decade before he appeared in LEGION.
He certainly wasn’t the big ol’ slab of beef he was later, in any case.
And an interior (where he kills off a parody of Fred Hembeck).
Yeah, that quote by the writer basically screams, “I don’t understand this character.”
I’ve always considered the Omega Men appearances a sort of “beta” Lobo. In any case, here’s what he looked like when he showed up for the first time in L.E.G.I.O.N.:
http://static.comicvine.com/uploads/original/9/98822/2154487-lobo2.jpg
I like the new Lobo, because the old one has turned into a joke.
Rather the opposite, really. He was created as a joke (a poke against Wolverine and such characters), and eventually became semi-serious.