I'm not well versed in the history of, but I think the deal is that Ryan Jenkins who was a contestant on Megan Wants a Millionaire and suspected of murdering his wife and then committed suicide was also a contestant on 3. As a result, VH1 never aired 3.
Around the same time all the Ryan Jenkins news was happening, VH1 was filming (and completed filming of)4, which VH1 originally planned to air in January 2010. Because of the controversy and the shelving of ILM 3, VH1 also cancelled I Love Money 4 as well.
But I Love Money 4 got uncancelled and finally made it on VH1 last Thursday September 16, 2010 from 11:01p-12:03a. It looks to me like VH1 just decided to quietly burn it off. No information about the show is promoted on VH1's web site. While I didn't see any demographic information, the premiere averaged 731,000 viewers last Thursday. That's a lot more than the 374,000 viewer average for "40 Greatest Pranks 2" at 11pm on Wednesday September 15, but for all I know that was the 500th time VH1 repeated "40 Greatest Pranks 2."