I like to bring my camera around where i go and travel.
i enjoy doing some photoshoot as well.
D90 i find it a little bit bulky esp when attached with a SB900 flash and 17-55 lens.
I thought of selling away my D90, to fund a M43.
Size is more and more of my concern now
other then M43, what other kind brand and make do you guy recommend for my kind of usage?
Smaller sized camera...
Nikon V1/J1 - it is a Nikon camera that you should have lots of experience in. And with the correct adapter, you can mount your Nikon lenses without losing AF capability... plus this two are among the smallest interchangeable lens camera you can find in the market.
Pentax Q - the smallest. And also the smallest sized sensor too. IQ is decent, but don't expect DSLR quality.
Pentax K-01 - large APS-C sensor (same or similar sensor used in the K-5), excellent image quality, quite small and light.
Olympus OM-D - currently one of the best m4/3 camera around, weather seal body, excellent image quality, fastest AF speed.
Olympus EP3/EPL3/EPM1 - all pretty small, and revolve around the same 12MP sensor that is pretty alright, but not excellent.
Panasonic GX1 - latest offering until the G5 was shipped. Pretty good IQ and pretty small too.
Panasonic G3/GH2 - great system but not exactly very small in size.
Sony NEX system- NEX 5n and the latest Nex 7, both have excellent APS-C sensor and have excellent IQ.
Fujifilm X-pro1 - In my opinion, it had the best IQ among the mirrorless... and I love the look of this camera... however AF has nothing to boast about... and to me that is a deal breaker.
Samsung NX20 - Latest offering by Samsung, do not have any experience with the Samsung but online reviews are pretty positive.
Of the above mentioned, X-Pro1, NEX-7 and OM-D costed the most, the rest had 1k to slightly (or alot) lesser than 1k (body only), EPM1 and EPL3 do not come in body only and you would have to get it together with a lens (I think Nikon's V1 and J1 too).
Other than the above choice, do take a long hard look at the following compact camera -
1) Canon G1X
2) Sony RX100