Quantum Leap has always been a cousin of Sliders...the earliest reviews of Sliders even noted the similarities. "Quantum Leap with an edge." But have you ever wondered if it went further than that? With the introduction of Maggie, it did.
As posted at the Sci-Fi BBoard by ThomasMalthus, there is a seemingly strong connection between Maggie and Sam Beckett. For those who watched Quantum Leap, you may remember the first two episodes of season three. Those episodes ("The Leap Home" and "Vietnam") gave us a glimpse of a relative Sam had who was only mentioned briefly before in the series. His brother, Tom.
In the original history before Sam leaped, Tom had died in 1970 Vietnam...but before "Vietnam" was over, Sam had saved his brother's life and changed history. Thus, a new history was made...one in which Tom presumably continued his career in the military.
But I know what you're saying...how does this connect to Maggie? Well, first of all...Maggie's last name is the same (even same spelling) as Sam's...Beckett. Sam's brother shared that name...and in 1970, his brother was in his early twenties, which would place Tom in his mid 50's by 1999. If his brother had survived and continued his military career...it is very plausible that Tom would be a general by that time.
In the season four episode "Slide By Wire", we learn that the name of Maggie's father was General Thomas Beckett. This is mentioned again in the season five episode "The Return of Maggie Beckett". Could it be that Maggie is in actuality the niece of Sam Beckett...the time traveling physicist?
I believe that at the very least, this is a nice inside homage placed into the show that many people will never catch. And while she may not be the niece of the Sam that we knew...Sam has countless doubles floating around out there just like everyone else...now doesn't he?