These are just the normal thoughts on the parsha, but I wanted to shake things up in the title department.
Reuven, the firstborn of Israel: the sons of Reuven: of Hanoch, the family of the Hanochites; of Pallu, the family of the Palluites... (26:5)
One interesting feature of the census in Pinchas is that the names listed are not always the same as those in Breishit 46:8-27, where Yaakov's sons and grandsons are listed. I think this discrepancy can be resolved by noting that point of the census is to list families, not sons. As can be seen from Bamidbar 26:53, the purpose of this census was to prepare for the allotment of land in Israel, which would be done by family. And it turns out that the families do not necessarily correspond one-to-one with the sons.
For a good example of this, look at the very highest level of family structure: the 12 tribes. One would expect that each of Yaakov's 12 sons would go on to father a tribe. Alas, things are more complicated. One tribe (Shimon) is eventually absorbed within another tribe (see Yehoshua 19:1 and 19:9), and loses its identity entirely. On the other extreme, Yosef becomes the father of two distinct tribes: Menashe and Efraim. Even at the tribal level, then, we see fluidity, as families split and merge and the resulting tribes do not match the family trees.
It's reasonable to assume that the same was true within each individual tribe. Thus the lists of families in our parsha should not necessarily correspond to the list of Yaakov's grandchildren earlier in the Torah. And indeed, we see that some of the families are named after Yaakov's great-grandchildren, while some of the grandchildren are not listed, and presumably their descendants joined other families.
UPDATE: From Ezra 2:61 we see that in some circumstances, family names can be chosen based on maternal rather than paternal descent. Thus providing one possible motivation for the aformentioned kind of change.
"Our father died in the desert. He was not among the group who gathered against Hashem, among Korach's group. Rather, he died due to his sin, and he had no sons. Why should our father's name disappear from his family, since he had no son? Give us a portion of land among our father's brothers." (27:3-4)
There have been various attempts to identify exactly which sin Tzelafchad died for. On a pshat level, I think this is misguided. The daughters are trying to show how their father was actually a worthy person who deserved to inherit land, and would have, except for the accident of not having sons. They clearly do not intend to draw attention to a particular failing of his.
Rather, I think we must keep in mind that EVERY person dies due to their sins. The daughters don't intend to refer to a specific sin for which he was killed, and probably couldn't name one if you asked them. They are just pointing out that he is dead, and doing it in such a way that they recognize God's justice in killing him. Quite possibly, "died due to his sin" was the normal expression a religious person at the time would use regarding any death. Thus the daughters strengthen their case, instead of weakening it by portraying Tzelafchad as a bad guy.
Regarding the broader context of this story, it seems worth noting the following parallel. Women in Tanach were not expected to take the initiative in sexual matters. But there was one glaring exception to this rule: yibum. When the woman's motivation was to preserve the name and status of her family, her sexual advances were not only allowed but encouraged. Thus we find Ruth approaching Boaz at night, Tamar dressing up as a prostitute to seduce Yehudah, and even Lot's daughters getting pregnant from him after their husbands die in Sedom. As outrageous as these acts are by normal standards, in the circumstances in which they occur, the Torah shows no sign of condemnation.*
Tzelafchad's daughters were seeking a legal injunction, not a sexual relationship, but their motivation was the same: to preserve the status of their family. As we have seen, the Torah respects this motivation to the point of allowing daring sexual conquests. So it is not surprising Tzelafchad's daughters' more legalistic request is granted.
* I first heard this from R' Yaakov Medan; see also here
"If a man dies without a son, you shall transfer [haavartem] his inheritance to his daughter. If he has no daughter, you shall give [netatem] his inheritance to his brother. If he has no brother, you shall give his inheritance to his uncle. If he has no uncles, you shall give his inheritance to his closest relative..." (27:8-11)
Note that a different word is used for when the daughter inherits.
There is a set hierarchy for inheritance, which predates this story and maybe predates the Torah entirely. In this hierarchy only men inherit. Inheritance acording to this normal hierarchy is referred to as "giving". But in the case of the daughter, the Torah overrides the hierarchy. The daughter's right to inheritance is external to the hierarchy - superimposed over it, rather than modifying it. The hierarchy still exists, unchanged. But in this case, we disregard it in favor of other considerations. When this happens, inheritance occurs through "transfer", not through the normal means of "giving".
And Moshe spoke to Hashem, saying: (27:15)
Another good article here. VBM was really on the ball this week.