I'm complaining because, as a twenty-year software developer, I know a simple thing like a memory leak is inordinately and comparatively easy thing to fix, and yet after three patches, its still not fixed. My save game is 14mb, but that's Bethesda's design. I collect a lot of stuff and I've done a lot of quests and accumulated a lot stats in game... that's Bethesda's design. If I had to rate it, I'd rate the lag as less in 1.1 than it was in 1.2, or less than is present in 1.3. But perhaps with v1.1 my character was still relatively young (read: small save file).
By all accounts, Bethesda has made over $600m in gross revenues on this game. There's an old addage in software development that says you can choose making software "fast, cheap or good: choose two". You can make software fast and cheap, but it won't be good. Or you can make it good and cheap, but it won't be done fast. And you can choose fast and good, but it won't be cheap. For pete's sake, throw some money at this problem!