Not really. There's new weapons with every installment and I don't think you could say Worms 3D and Worms 4 are the same as the early ones. Worms 2 Armageddon on PSN and LIVE is not as good as most Worms games but still decent.
The original (Worms) was more fun and less aggravating. they messed it up afterwards, now it just doesn't seem as responsive and the wind always blows too hard.
Yeah and in Madden you get new modes... and songs! I'm actually impressed in how the Madden crew rehash the same initial game every time. It's not like Football ever changes... and I don't get the criticism, if you like Football (American) you like Football. It's not the same every year because of the stats. Just saying what makes Madden interesting is the stats, who's your stars this time, who are you gonna plan your attack around?? I don't mind playing the same old game over and over if your focal point changes a lot of the time. In Worms however, it's always just 'who has the biggest gun' or 'who is the sneakiest'. If each Worm had a different stat, if there were scout worms, engineer worms, strongman worms and so on... I might differ... but... it's just the same game every time, sure they add weapons, but it's always 'who can overwhelm who first'.
Steam has Anomaly: Warzone Earth for $3.33 I guess it's like a tower defense but you play the convoy rather than the towers.