counting sefirah, counting years to yovel

1) Tzror haMor writes that there is a connection between the opening of week's parsha and the conclusion of last week's.  The end of last week's parsha told us about the person who was mevarech Hashem and who disrespected Moshe's authority.  Just like you must have kvod Shamayim and respect kvod talmidei chachamim, so too, writes Tzror haMor, our parsha teaches us that the land of Eretz Yisrael is holy and requires the same respect and kavod.  

2) Rabeinu Yerucham compares the counting of sefiras ha'omer to the counting of shemitah cycles and years leading up to yovel.  Just like after 49 years we are mekadesh the yovel year, so too, after 49 days we are mekadesh the 50th day as the holiday of Shavuos.

R' Berel Povarski suggests that the analogy is not just derush b'alma.  

The Rambam opens hil shemita with the din

מצות עשה לשבות מעבודת הארץ ועבודת האילן בשנה שביעית

And in perek 10 he writes with respect to yovel

מצות עשה ***לספור שבע שבע שנים ו*** לקדש שנת החמשים

Note that with respect to shemita, the Rambam does not mention the need to count six years in order to get to year 7, but he mentions the need to count seven shemitot to get to a yovel.  Tos (Menachos 65b d"h u'sefartim) writes that there may even be a chiyuv on B"D to recite a bracha and count each year (R' Akiva Eiger mh"k 29,30 is medayek otherwise from the Ran at the end of Pesachim).  

The seventh year of shemita happens even if no one counts the previous six.  Yovel, however, only comes if there is a count of 49 years beforehand to lead to it.

Meshech Chochma on our parsha draws a comparison between shemita and Shabbos and yovel and Yom Tov.  The kedusha of Shabbos is "kevi'a v'kayma;" it does not need a mekadesh.  The kedusha of Yom Tov depends on beis din sanctifying that period of time and designating it as the chag.  Yovel needs a count in order for it to happen; it does not take effect on its own.

The Rambam (Shemtia 10:5) quotes a mesorah from the Geonim that between bayis rishon and bayis sheni only shemitah and not yovel was observed, and the same, of course, was true post-churban.  If yovel was suspended because celebrating yovel is only done when "kol yoisheveha aleha," the majority of Jews live in Eretz Yisrael, then it should not have been observed for many years earlier than the bayis rishon/sheni interregnum?

R' Chaim (al haRambam) explains that there is a difference between observance of yovel and the count of yovel.  Even if in practice none the halachos of yovel can be fulfilled, so long as beis din is functioning and can count years, year 50 will be yovel and the next 49 year cycle will start the year afterward.  Only when there is no beis din to count, which happened during the interregnum period, year 50 is skipped and one 49 year cycle will follow immediately the prior one.

Coming back to Rabeinu Yerucham, now that we understand the the count of years to yovel is necessary for yovel to happen, it's parallel, sefiras ha'omer, takes on additional significance as not just marking time, but as a necessary preparation period without which Shavuos would not have the same meaning.