The 14-140 lens that comes with the GH1 is an amazing lens.  Really crisp shots.  It's not enough zoom for us so we went to the 45-200mm lens and it's great too.  

Rumor has it the Panasonic has a 100-300mm lens in the works.  If so, we'll be all over it!  We need more zoom for our air show shots.

There are a lot of adapters out there that allow using other brand lenses - like Nikon, Canon, Olympus, etc.  The problem is you won't get all the features, like auto focus or image stabilization.  That makes for some cool options but we're sticking with Panasonic lenses because we need AF and OIS.

hope this helps!

Tim

SO in addition to the 45-140 which came with my G1, I got my hands on a 45-250mm (H-FS045200).  Love it.

NOw I'm trying to get one of the pancake lens (H-H020).  Fixed lens F1.4, would make awesome portraits..  But for the love of trying.  NO-one seems to have it.  They're all backordered (seems Panasonic bundled them ALL with the GF1s...hmmph)...with the exception of ordering from Japan on ebay (at almost 2x the price).

So apart fomr that frustration, and no real news of new lens on the way just yet,  keep referring to this site. http://www.panasonic.net/avc/lumix/systemcamera/gms/lens/index.html.

So even though i'm now beginning to enter this photography thing... the advice i got was to get the 45-250 lens next...which gives you a lot more flexibility... then you cna look inot getting a macro lens or a pancake.  (which reminds me... I really need to put my pics up.)

Oh... are you able to use the RW2 format on your computer?  (i.e. on a mac?)   :(

-E